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As the Zhurong rover landed on the surface of Mars in 2021, it began a months-long collection of Mars data. Equipped with highly sensitive sensors, Zhurong is capable of being a meteorological station at the surface of Mars. The Mars Climate Station, one of the onboard sensors with high sensitivity, helps the Tianwen-1 lander to collect meteorological data at the Martian surface, via which the air temperature, atmospheric pressure, wind speed and direction are measured. In this paper, we present results of surface pressure, air temperature and wind data from the Mars Climate Station at Zhurong's landing site. The data is collected in 176 solar days out of the entire rover's mission time, 325 solar days. We use a trigonometric function to fit the relationship between the solar longitude (Ls) and the pressure, after which we compare the results with those of Viking I. Our analysis of the temperature shows that seasonal evolution is similar to the patterns concluded in previous Mars missions at different landing sites. We discover that wind speed appears the maximum in early summer near Zhurong's landing site, and analyze the occurrence of dust storms by combining the data of wind and temperature. Our results provide some evidence of the seasonal changes in meteorological pattern at Tianwen-1's landing site, south of Utopia Planitia. With the mission ongoing further, more results are expected in the future. [ABSTRACT FROM AUTHOR]

Wearable and implantable electronic (WIE) devices are enabling a new generation of customized real-time health monitoring systems. Some of the highest performance systems involve MOSFET-based sensors as well as MOSFET-based digital and analog circuits. Protecting these transistors in a harsh fluidic environment is difficult because the requirement of wearability/flexibility demands ultrathin encapsulation. The charged ions (such as Na+) from body-fluids can diffuse rapidly through the thin encapsulation layer and destabilize the transistors, and render the component nonfunctional. In this paper, we develop an analytical framework and scaling theory for Na+ penetration into the encapsulation layer of WIE devices. Coupled with the physics of MOSFET degradation, the ion penetration model predicts lifetime of MOSFET-based electronics encapsulated by various types of encapsulating materials. The model is easily generalized to include multiple design parameters, such as stacks of encapsulation layers, encapsulation layer thicknesses, temperature/field dependent ion drift, and rate of dissolution of the encapsulation layer. Our simulations and experiments show that: 1) a multilayer encapsulation is essential to achieve multiobjective passivation, and 2) the encapsulation thickness must be optimized by accounting for charged ion penetration and dissolution of the encapsulation layer. [ABSTRACT FROM PUBLISHER]

In this work, a kind of negative capacitance double-gate junctionless transistor (NC-DG-JLT) with ferroelectric (FE) gate dielectric and metal-ferroelectric-metal-insulator-semiconductor (MFMIS) structure is proposed. It is demonstrated that NC-DG-JLTs can lower off-state current, improve on-state drain current, and lower subthreshold swing at the same time compared with its conventional DG JLT counterpart using numerical simulation. The steep subthreshold swing ( SS < 60 mV/dec) is achieved at room temperature. The related physical mechanisms are discussed in detail. The low off-state current and high on/off current ratio could be obtained even for ultra-small transistors by optimizing the device parameters. NC-DG-JLTs have a great potential for low power dissipation applications. [ABSTRACT FROM AUTHOR]

Herein, we reported a gas sensor based on MXene/Graphene composite sensitive film for low-concentration ammonia detection. Specifically, we use the electrophoretic deposition method to uniformly deposit MXene on the graphene film surface of the graphene sensor, thereby constructing the MXene/Graphene composite sensitive film. The ammonia sensitivity test results show that the MXene/Graphene composite film sensor exhibits fast response, high sensitivity and excellent selectivity to ammonia at room temperature and high humidity. At the same test concentration (100 ppm), the sensitivity of the MXene/Graphene sensor is 3 times higher than that of the graphene sensor, 2 times higher than that of the MXene film sensor, reaching 25%, and its theoretical limit of detection is 56 ppb. The response time is only 26 s and the recovery time is 148 s, while the response time of the graphene sensor is 228 s. The MXene/Graphene sensitive film takes full advantage of the hydrophilicity and abundant surface functional groups of MXene, and the excellent electrical conductivity of graphene, which solves the problems of low sensitivity, slow response speed, and inability to completely desorb ammonia gas of pure MXene or graphene. Potential applications in designing next-generation portable gas sensors for human breath detection analysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Encryption is an important step for secure data transmission, and a true random number generator (TRNG) is a key building block in many encryption algorithms. Static random-access memory (SRAM) chips can be easily available sources of true random numbers, benefiting from noisy SRAM cells whose start-up values flip between different power-on cycles. Embarking from this phenomenon, a novel performance (i.e., randomness and throughput) improvement method of SRAM-based TRNG is proposed, and its implementation can be divided into two phases: irradiation exposure and hardware postprocessing. As the randomness of original SRAM power-on values is fairly low, ionization irradiation is utilized to enhance its randomness, and the min-entropy can increase from about 0.03 to above 0.7 in the total ionizing irradiation (TID) experiments. Additionally, while the data remanence effect hampers obtaining random bitstreams with high speed, the ionization irradiation can also weaken this impact and improve the throughput of TRNG. In the hardware postprocessing stage, Secure Hash Algorithm 256 (SHA-256) is implemented on a Field Programmable Gate Array (FPGA) with clock frequency of 200 MHz. It can generate National Institute of Standards and Technology (NIST) SP 800-22 compatible true random bitstreams with throughput of 178 Mbps utilizing SRAM chip with 1 Mbit memory capacity. Furthermore, according to different application scenarios, the throughput can be widely scalable by adjusting clock frequency and SRAM memory capacity, which makes the novel TRNG design applicable for various Internet of Things (IOT) devices. [ABSTRACT FROM AUTHOR]

• The equilibrium points of asteroid 4660 Nereus and their stability are analyzed. • Potentially long-lifetime orbit families in Nereus neighborhood are identified. • Inclined heliotropic orbits and terminator orbits are found to be more stable. • The impact of the SRP, asteroid gravity and polar direction is investigated. Spacecrafts operating in close proximity to small celestial bodies within our Solar System, such as asteroids, face dynamic environments that differ significantly from those encountered in the near-Earth space. Understanding the characteristics of orbital dynamics in the vicinity of asteroids is essential for the successful execution of asteroid exploration missions. Focusing on the asteroid 4660 Nereus, this paper studies the equilibrium points of it and the potentially natural, long-lifetime orbits subject to perturbations from both the asteroid's non-spherical gravitational field and the solar radiation pressure (SRP). Using the semi-analytical method based on averaged Lagrange planetary equations (LPEs), heliotropic and terminator orbits are found more likely to have long lifetimes. It is noteworthy that the conventional near-equatorial heliotropic orbits around Nereus struggle to maintain a long lifetime. In contrast, orbits characterized by a specific inclination and geometry where the apocenter approximately points toward the Sun tend to offer prolonged lifetimes. Moreover, the impact of variations in SRP, gravitational parameter, and pole direction on feasibility of long-term orbit solutions has been explored, resulting in an enhanced comprehension of the intricate orbital dynamics. This study contributes valuable insights for the design of exploration orbits in the vicinity of the Nereus asteroid. [ABSTRACT FROM AUTHOR]

Layered double hydroxide (LDH) is frequently used for phosphate removal in water, while a desirable LDH adsorbent should have sufficiently high adsorption capacity and selectivity. To enhance the removal performance and selectivity of phosphate by LDH, La-doped layered double hydroxide/biochar (La–MgAl–LDH/BC) was synthesized by using a co-precipitation method. Investigation results showed that lanthanum (La) metal loading can significantly enhance the phosphate adsorption performance of La–MgAl–LDH. Then, the introduction of La–MgAl–LDH into BC improved the adsorption capacity of phosphate by the adsorbent, which is 1.8 times that of pure La–MgAl–LDH. The optimum La to Al molar ratio was 0.2 : 0.8 in La–MgAl–LDH materials, and the La–MgAl–LDH to BC mass ratio was 9.3 : 10. Furthermore, both La–MgAl–LDH and La–MgAl–LDH/BC exhibited an enhanced ability to resist interference from co-existing anions (Cl−, SO42−, NO3− and CO32−) compared to LDH. For batch experiments, the kinetic results indicated that the adsorption process of phosphate by La–MgAl–LDH/BC follows a pseudo-second-order kinetics model, reaching equilibrium quickly within 1 h. Furthermore, film diffusion and intra-particle diffusion simultaneously took place. The maximum monolayer phosphate adsorption capacity of La–MgAl–LDH/BC could reach 249.3 mg PO43− g−1 (513.6 mg PO43− g−1, converting to an equivalent La–MgAl–LDH). After four cycles, La–MgAl–LDH/BC showed good reusability, and over 63.5% of phosphate uptake was retained with minimal metal leaching. Additionally, phosphate could be rapidly removed from actual water and simulated water at low concentrations. The electrostatic attraction, ligand exchange, ion exchange and Lewis acid action jointly facilitate the adsorption of phosphate. [ABSTRACT FROM AUTHOR]

The ammonia (NH 3)-sensing performance of phosphorus-doped graphene sensors is systematically investigated in this paper. Using a chemical vapor deposition (CVD) system, phosphorus pentoxide was used as the phosphorus source to achieve stable phosphorus doping of graphene at 480 oC. The NH 3 -sensing test results showed that the NH 3 response of phosphorus-doped graphene increased by 2.4 times on average, the response (recovery) time shortened by 70.6% (73.4%) on average, and the theoretical limit of detection (LOD) was 68.76 ppb. In addition, the phosphorus-doped graphene sensor also exhibits excellent repeatability, stability, and ultra-high selectivity to NH 3. XPS, EDS, and FTIR analysis show that the P-O groups introduced on graphene are the key to improving the NH 3 sensitivity of graphene. The P-O groups provide sufficient O atoms to assist graphene to adsorb NH 3 molecules, thereby improving the NH 3 sensitivity of graphene. A simple, large-scale implementable, and effective phosphorus doping by the CVD method was proposed to improve the NH 3 sensitivity of graphene in this work, which is of great significance for promoting the practical application of graphene gas sensors. • After phosphorus doping, the NH 3 response of graphene sensor increased by 2.4 times. • The detection limit of the phosphorus-doped graphene sensor towards NH 3 is 69 ppb. • The response time of phosphorus-doped graphene sensor shortened by 70.6%. • Low-cost and stable phosphorus doping of graphene is achieved at 480 °C by CVD. [ABSTRACT FROM AUTHOR]

AlGaN/GaN‐based high electron mobility transistors (HEMTs) are ideal candidates for power electronics in consumer, industrial, and space applications. Attributed to their excellent performance in electrical output and chemical stability, AlGaN/GaN HEMTs enable tolerant neutron irradiation in harsh environments. Different from high‐fluence irradiation‐induced device failure, the investigation of low‐fluence neutron irradiation is of great significance to understand the early damage mechanism of HEMTs. Here, the modulated electrical properties are presented of AlGaN/GaN HEMTs under low‐fluence neutron irradiations of 4.5 × 1013 and 6.0 × 1013 cm−2. After irradiation, the electrical characteristics of the samples are carefully measured, the output performance of different irradiated devices shows a similar change trend, i.e., almost no changes or only decreased slightly (≤14%) near the knee voltage. For leakage current, the samples irradiated with different fluences show different characteristics, including a slight decrease with the fluence of 4.5 × 1013 cm−2, and a slight increase with the fluence of 6.0 × 1013 cm−2. To further investigate the internal mechanisms, the performance changes are also simulated of the device by using Crosslight software. According to the measurements, it is concluded that the low‐fluence neutron irradiation will initially affect the 2DEG mobility and the surface states of the HEMTs. [ABSTRACT FROM AUTHOR]

With the development of aerospace science and technology, more and more probes are expected to be deployed around extraterrestrial planets. In this paper, some special orbits around Jupiter, Saturn, Uranus, and Neptune are discussed and analyzed. The design methods of some special orbits are sorted out, considering the actual motion parameters and main perturbation forces of these four planets. The characteristics of sun-synchronous orbits, repeating ground track orbits, and synchronous planet orbits surrounding these plants are analyzed and compared. The analysis results show that Uranus does not have sun-synchronous orbits in the general sense. This paper also preliminarily calculates the orbital parameters of some special orbits around these planets, including the relationship between the semi-major axis, the eccentricity and the orbital inclination of the sun-synchronous orbits, the range of the regression coefficient of the sun-synchronous repeating ground track orbits, and the orbital parameters of synchronous planet orbits, laying a foundation for more accurate orbit design of future planetary probes. [ABSTRACT FROM AUTHOR]

• Preparation of ZrO 2 by sol–gel method and first discovery of negative set phenomenon. • Negative se't phenomenon was found to be caused by oxygen vacancies. • Insertion of NiO layer effectively eliminates device negative se't phenomenon. • NiO insertion layer greatly improve the switching property of the RRAM device. Resistive random-access memory (RRAM) is a promising non-volatile memory technology due to its fast operation, low power consumption, and high reliability. However, the negative set phenomenon remains a challenge for RRAM, which can lead to the deterioration of device switching parameters. In this study, we successfully addressed this issue by inserting a NiO blocking layer between the ZrO 2 and Ag top electrodes in ZrO 2 -based RRAM. In addition, the resistive switching characteristics of the device are significantly enhanced by the incorporation of a p-type oxide NiO layer. Compared to single-layer ZrO 2 devices, the double-layer Ag/NiO/ZrO 2 /ITO RRAM exhibits improved cycling durability (>500 cycles) and good retention time (3 × 104s). Our analysis of the device conduction mechanism and proposed resistive switching model suggest that oxygen vacancies play a connecting role in the reset process, leading to failed reset behavior. Through the incorporation of a p-type semiconductor NiO layer into ZrO 2 -based RRAMs, the interference of oxygen vacancies on the reset process can be effectively impeded. This approach not only provides an effective resolution to the unforeseen negative set phenomenon in RRAM devices, but it also holds paramount significance for the advancement of high-performance RRAMs. [ABSTRACT FROM AUTHOR]

In this work, the acetaldehyde (CH 3 CHO) sensing performance of Copper(II) oxide nanoparticles/reduced Graphite oxide/Graphene composite structure (CuO NPs/rGO/G) was systematically studied. Firstly, CuO NPs/rGO composite nanostructures were prepared by hydrothermal synthesis, Then, CuO NPs/rGO was uniformly deposited on graphene film to prepare CuO NPs/rGO/G composite structure. CH 3 CHO sensing tests have shown that the CuO NPs/rGO/G composite structure exhibits a fast and highly sensitive response to CH 3 CHO at room temperature. At the test concentration of 100 ppm CH 3 CHO, the response of CuO NPs/rGO/G composite structure is 39.94 times that of graphene, 11.37 times that of CuO NPs/rGO, and 5.90 times that of CuO NPs, up to 82.67 %. The response time is only 22 seconds, the recovery time is 159 seconds, and its theoretical limit of detection is 95.10 ppb. In addition, the CuO NPs/rGO/G composite structure has excellent selectivity, repeatability, and long-term stability for the sensing of CH 3 CHO. The CuO NPs/rGO/G composite structure studied in this paper solves the problems of poor response, slow response, slow desorption and even inability to desorption of graphene in CH 3 CHO sensing, and has great application potential in respiratory VOCs detection, environmental harmful gas detection, etc. • The response of the CuO NPs/rGO/G sensor to CH 3 CHO is 39.94 times that of graphene. • The detection limit of the CuO NPs/rGO/G sensor towards CH 3 CHO is 95.1 ppb. • The response/recovery time of CuO NPs/rGO/G sensor is 22 s and 159 s. • Realized rapid and highly sensitive sensing of CH 3 CHO at room temperature. [ABSTRACT FROM AUTHOR]

Preclinical Research The quest for a well ‐ validated, non ‐ invasive biomarker to aid in clinical decision making has remained elusive in the cancer space over the last 30 years. Much promise has been attached to circulating tumor cells (CTCs) as prognostic, predictive, and pharmacodynamic biomarkers with the potential to eliminate the need for invasive tumor biopsies and improve on the clinical value of other circulating tumor markers. The CellSearch® system (Veridex, LLC., Raritan, NJ, USA) cleared the U.S. Food and Drug Administration when the presence of CTCs was shown to have prognostic significance in patients with breast, prostate, and colorectal cancer. However, CTCs are not, at present, routinely being used in the clinic to guide treatment decisions. This paper discusses key attributes that a biomarker must possess, the status of other potential cancer biomarkers, and advancements in the capture and characterization of CTCs that will enable actualization of their potential as a reliable and efficient biomarker of disease diagnosis, progression, and response to therapy in the clinic. [ABSTRACT FROM AUTHOR]

We develop a plasma-assisted nitrous-oxide (N 2 O) gas oxidation (PANO) method to prepare the ultrathin silicon oxide (SiO x) for polysilicon (poly-Si) passivated contact. The effects of preparation conditions, including the substrate temperature, processing time, and plasma power, are studied. Afterwards, we integrate the PANO SiO x into the polysilicon passivated contact and optimize the passivation and contact performances. Excellent surface passivation with the n-type poly-Si and PANO SiO x on the n-type c-Si wafer is achieved by 880 °C annealing, which shows competitive passivation quality to the one with NASO SiO x. Champion implied open-circuit voltage (i V oc) and single-sided recombination saturated current (J 0) reach 730 mV and 4.3 fA/cm2 after crystallization; and they are further improved to 747 mV and 2.0 fA/cm2 (3 × 1015cm−3) after subsequent AlO x /SiN x hydrogenation. Using transmission electron microscopy (TEM), we find that the thickness of PANO SiO x ranges 1.1–2.4 nm and the controlled nitric acid oxidized SiO x (NAOS) ranges 1.3–1.8 nm. The contact resistivity (ρ c) is typically <10 mΩ cm2 with the annealing temperature of >820 °C. Also, the crystallinity, phosphorous in-diffusion profile, and current-leaking density of the passivated contacts are investigated. In general, the PANO SiO x and in-situ doping amorphous silicon precursor can be fabricated in one PECVD system without additional equipment or transfer procedures, which is favorable for the high-efficiency, low-cost industrial manufacture. • Ultrathin SiO x prepared by in-line plasma-assisted N 2 O oxidation (PANO) is used for passivated contact. • Passivated contact with PANO SiO x shows competitive quality to that with NASO SiO x. • Champion surface passivation reaches i V oc = 747 mV & J 0 = 2.0 fA/cm2 after hydrogenation. • Contact resistivity becomes <10 mΩ cm2 if annealing temperature is > 820 °C. • Oxidation degree, thickness, and pinhole are characterized for robust passivated contact with PANO SiO x. [ABSTRACT FROM AUTHOR]