Extremely Low Temperature Research Articles

Fully Conjugated Anthraquinone‐Quinoxaline Derivative Cathode Enabling a Superior Zn‐Ion Storage at Extremely Low Temperature −50 °C

AbstractSmall molecule organic materials have been considered promising candidates as cathodes in aqueous zinc‐ion batteries (AZIBs) because of their low cost, environmental friendliness, and sustainable production. However, the rapid capacity fading and sluggish kinetics restrict their practical applications, especially under extremely low temperatures (−50 °C). Here, by the condensation of hexaketocyclohexane octahydrate (HKCO) and 1, 2‐diaminoanthraquinone (DQ), a fully conjugated organic molecule, anthraquinone‐quinoxaline derivative (HATAN) is prepared. With the fully conjugated structure, HATAN possesses enhanced π‐electron delocalization and strong intermolecular interaction, which ensure superior electronic conductivity and physicochemical/electrochemical stability. Additionally, the introduction of multiple redox‐active sites (C═O and C═N) can increase the theoretical capacity of HATAN. Consequently, the HATAN cathode for AZIBs exhibits remarkable capacity, long lifespan, and high‐rate capability. Even at −50 C, an exceptional capacity of 75.4 mAh g−1 and 98% capacity retention over 1500 cycles can be preserved. This study presents valuable insights into the structure design of small molecule organic cathodes for advanced AZIBs which can efficiently operate at −50 °C.

The Impact of Extreme Temperatures on Grain Production in the Huaihe River Basin

The Huaihe River Basin is an important major grain producing area in China, maintaining the stability of grain output is of great significance to food security. However, with global warming, the frequency of extreme temperature events has increased, and the frequent meteorological disasters have brought great challenges to the stable supply of food production. In this paper, the impact of extreme temperature on grain production in the Huaihe River Basin was analyzed by using the daily temperature and agricultural production related data of 28 prefecture-level cities in the Huaihe River Ecological Economic Belt from 2001 to 2020. The following conclusions are drawn: 1) The influence coefficient of extreme high temperature on grain production in the Huaihe River Basin is -0.021, extreme low temperature has no significant impact on food production. 2) The effects of extreme temperature on food production in different regions in the river basin were heterogeneous, but the overall impact was negative. The influence coefficients of extremely high temperature days on the eastern region and Midwest region were -0.035 and -0.052, respectively, while the influence coefficients of extremely low temperature days on the eastern region were -0.413. The results showed that the increase in the number of extremely high temperature days would reduce production in the eastern region andMidwest region of the basin, while the northern region was not significantly affected by extreme heat. The increase in the number of extremely low temperature days will reduce grain production in the eastern region, and the impact on the Midwest region and the northern region will not be significant. Based on the above conclusions, three suggestions are put forward to maintain the safety of food production in the Huaihe River Basin: 1) enhance the ability to detect climate change in the basin; 2) Protect the stability of grain cultivated land in the river basin; 3) Innovative breeding of climate-resilient food crop seeds.

Tensile testing at the Extremely Low Temperature of 6K : Microstructure and Mechanical Properties of a Fe-Mn-Cr Steel

Materials with superior cryogenic strength and good ductility are increasingly in demand for resident friendly liquid-hydrogen (20K) storage tanks. Additionally, the space industry also requires materials that retain excellent mechanical properties at extremely low temperatures. However, mechanical testing at such low temperatures is highly limited due to the difficulties in achieving and maintaining such conditions, while also providing adequate thermal insulation to prevent heat transfer from the surrounding environment. In this study, we present a novel tensile testing technique for a Fe-15Mn-13Cr-3Si-3Ni-0.1C (wt.%) steel at the temperature of liquid helium. To minimize the use of expensive liquid helium, we adopted a method of injecting liquid helium vapor and set the temperature for tensile testing at 6 K. The present alloy has a single face-centered cubic (FCC) structure with a large amount of stacking faults after annealing treatment. The Fe-Mn-Cr steel exhibited a superior ultimate tensile strength of 1200 MPa and good ductility of 35% at 6K. Moreover, compared with room temperature tensile tests, discontinuous plastic flow, i.e. serrated flow, occurred at extremely low temperature.

Effects of sowing patterns on nitrogen utilization and yield formation of winter wheat in the western Huang-Huai-Hai region.

To examine the differences of three improved sowing methods in winter wheat yield and nitrogen efficiency and reveal the characteristics responsible for such differences, we conducted field experiments in the Jinnan area of the western Huang-Huai-Hai wheat region for three consecutive seasons from 2016 to 2019. The three improved sowing methods were wide space sowing (WSS), furrow sowing in moisture soil (FS), and three-dimensional uniform sowing (TDUS), with conventional drilling sowing (CDS) as the control. The results showed that meteorological factors such as accumulated temperature, solar radiation, and precipitation in the growing seasons from 2016 to 2019 showed great intra- and inter-annual variations. Compared with CDS, the improved sowing methods (WSS, FS, and TDUS) enhanced spike number per unit area and increased grain yield in three growing seasons by 18.3%-55.5%, 8.6%-22.2%, and 10.9%-39.5%, respectively. The three methods increased nitrogen uptake efficiency (NEup) by 5.8%-57.1%, pre-flowering nitrogen transfer ratio (Np/Nt) by 3.0%-15.3%, and nitrogen efficiency by 7.9%-35.7%, respectively. We developed a structural equation model (SEM) by integrating meteorological factors and experimental variables. The results showed that the three improved sowing methods could reduce the effects of extreme low temperature on wheat plant population, increase NEup and Np/Nt, and provide sufficient nitrogen supply to the grains of high-spike number wheat population for high yield and high nitrogen efficiency. In summary, our results demonstrated that WSS, FS, and TDUS all improved NEup and Np/Nt in the 2016-2017 season when meteorological conditions were favorable for wheat growth, and enhanced yield components with high SN, leading to high yield and high nitrogen efficiency. In contrast, in both 2017-2018 and 2018-2019 seasons with extremely low temperature and uneven distribution of meteorological conditions, WSS had a higher number of tillers at the jointing stage and enhanced pre-flowering nitrogen uptake and translocation, whereas TDUS had a relatively stable nitrogen uptake rate, leading to a stable grain yield.

PO-04-041 EFFICACY OF BALLOON EXPANDABLE EXTREME-LOW TEMPERATURE "XLT" VENTRICULAR EPICARDIAL CRYOABLATION: A PRE-CLINICAL DOSE RANGING STUDY

Lack of transmural lesion formation with catheter or surgical ablation for ventricular tachycardia (VT) can be an important determinant of arrhythmia recurrence. The aim of this study was to evaluate the feasibility and efficacy of a novel balloon expandable extreme-low temperature (XLT) cryoablation device for epicardial ventricular ablation. A total of six healthy Yorkshire swine (63 ± 6 kg) underwent surgical epicardial access. Four-to-five right (RV) and left (LV) ventricular epicardial targets were identified: anterior (1-2), lateral (1-2), summit (1-2). Ablation was performed with the novel 'XLT-cryo' device (HeartPad®Mini, Corfigo, Montclair, NJ), a balloon-expandable epicardial device that circulates extremely cold helium (∼ -253C) at a high flow rate through a flat pad with dimensions of ∼15 x 15mm. It is mounted onto the surface of an ∼30mm insulation balloon with blunted ends for fixation and parietal pericardial protection. At the end of each timed ablation, a thaw cycle was initiated to warm the device and allow repositioning to the next target. Ablation lesion size was measured using TTC staining. A total of 27 epicardial lesions were created (RV: n=2; LV: n = 25). The average lesion depth increased with time and reached complete transmurality with a plateau at 1 minute (time [T; sec] and mean depth±stdv [mm]; T15=11±0.5, T30=12±1, T60=15±1, T120=16±0.5, T240=17±0.5; Figure). Lesion transmurality was achieved in all lesions with ablation time ≥2 min. Lesion geometry was similar across different RV/LV locations, including the LV summit. Ventricular fibrillation (which is common in Yorkshire swine) occurred during/following 3 applications out of 27. Our results indicate that epicardial cryoablation using the novel balloon expandable HeartPad® device with extremely low temperature applications can efficiently produce transmural ventricular lesions in different epicardial locations. This technology holds potential for both surgical and catheter-based VT ablation in humans.

The change in the relationship between temperature and respiratory diseases among children in Guangzhou, China.

Temperature is closely associated with respiratory disease (RD) in children, but few studies have examined whether the relationship between ambient temperature and RD in children changed after the COVID-19 epidemic. The aim of this study was to assess the relationship between temperature and RD in children after the COVID-19 epidemic in Guangzhou, China. We used a distributed lag nonlinearmodel to compare the relationship between temperature and RD among children in Guangzhou from 2018 to 2022. The results showed an S-shaped relationship between temperature and RD in the post-COVID-19 period with a reference minimum risk at a temperature of 21°C and an increasing relative risk (RR) at extremely low temperature (ELT) and extremely high temperature (EHT). The highest RR associated with EHT was 1.935 (95% confidence interval [CI]: 1.314-2.850) at a lag of 0-14days. The on-the-day lag effects were found to be strongest at the lag 0day of EHT with a RR of 1.167 (95% CI: 1.021-1.334). Furthermore, each 1°C increase in post-COVID-19 temperature increased the risk of RD by 8.2% (95% CI: 1.044-1.121). Our study provides evidence that the relationship between temperature and RD in children in Guangzhou changed after the COVID-19 epidemic, and high temperature is more likely to cause RD in children. Relevant government departments and parents should understand the relationship between temperature and RD in children and develop new preventive measures.

The Collaborative Optimization of the Discharge Pressure and Heat Recovery Rate in a Transcritical CO2 Heat Pump Used in Extremely Low Temperature Environment

Considering the excellent environmental properties and heating capability under wide running conditions of the natural fluid CO2, the transcritical CO2 heat pump system has widely been used in the application of water heaters, commercial heating and cooling, electric vehicle thermal management, etc. Since the performance was highly affected by the discharge pressure and heat recovery rate in a transcritical CO2 system, the collaborative optimization of these two parameters was analyzed in detail in this study. The results showed that the optimal value of the system heating COP, which was the ration of heating capacity to power consumption, was better under a higher heat recovery rate and relatively lower discharge pressure, which is why these kinds of operating conditions are highly recommended from the perspective of collaborative optimization. Additionally, the heat recovery rate had a positive effect on the system performance when the discharge pressure was lower than its optimal value, while the heat recovery rate would present a passive effect on the system performance when the discharge pressure was higher than its optimal value. The relevant conclusions of this study provide a good theoretical basis for the efficient and stable operation of the transcritical CO2 heat pump technology under the conditions of a wide ambient temperature range.

An improved model assessing variation characteristics of pore structure of sandy soil thawing from extremely low temperature using NMR technique

During the construction of subway connecting passages in major cities in China, in last decades the artificial freezing method has gradually been becoming one of the most safe and effective methods in excavating saturated sandy soils. This work aims at exploring the changes of pore size and relaxation time induced by temperature change using NMR technology. Sandy soil samples were retrieved from a subway construction site in Beijing. In the laboratory experiments, these samples were loaded by different extremely low temperatures and natural convection thawing. The T2 (i.e., relaxation time) distribution curves and real-time temperature throughout the thawing process were recorded. It was observed that the variation of T2 distribution curves and pore structure changes with temperature may be divided into four stages, i.e., Stage I: spherical and cylindrical pores with radius r = 0.3 nm are formed at temperature lower than −28.0 °C; Stage II: the water adsorbed in pores melts and pore radius increases to the range of 0.3 nm < r < 32.0 nm as temperature increases in the range of −28.0 °C ∼ -0.2 °C; Stage III: capillary water in the pores with radius >32.0 nm melts rapidly as temperature increases in the range of −0.2 °C ∼ 0.7 °C; Stage IV: small amount of pores transform from small-sized absorptive pores and large-sized capillary pores to medium-sized absorptive pores as temperature increases to above 0.7 °C°. The specific threshold temperature and the threshold relaxation time are found as −0.2 °C and 5.17 ms respectively. By quantitatively analyzing the incremental change of T2 distribution curves and the rising temperature, an improved Gibbs-Thomson equation and a Two-Staged model of T2LM-Tmel (the geometric mean of relaxation time - the absolute value of temperature) and T2-Tmel (relaxation time - the absolute value of temperature), which are applicable to NMR technology, were proposed. Based on these results, a new pore structure evolution model of frozen sandy soil thawing from extremely-low temperature was proposed.

Surface Chemical Modification of Nanoparticles at Solid State in Vacuum at Extremely Low Temperature without Catalyst and Solvent

Surface Chemical Modification of Nanoparticles at Solid State in Vacuum at Extremely Low Temperature without Catalyst and Solvent

Artificial Ground Freezing Impact on Shear Strength and Microstructure of Granite Residual Soil Under an Extremely Low Temperature

The Artificial Ground Freezing (AGF) method, which is widely used in tunnel excavations, significantly affects the properties of geotechnical materials in frozen walls under extremely low temperatures. In order to simulate the AGF process, the freezing treatment with a temperature of −30°C and thawing treatment temperature of 25°C were performed on natural specimens of granite residual soil (GRS). Subsequently, triaxial (TRX) tests were conducted to evaluate mechanical properties and Nuclear Magnetic Resonance Image (NMRI) tests were applied to detect pore distributions of GRS. To clarify variations of microstructure after freezing-thawing, the relaxation time (T2) distribution curves and T2-weighted images from NMRI results were thoroughly analyzed from the perspective of quantization and visualization. Results show that the shear strength as well as the cohesion of GRS are reduced sharply by the AGF process, while the internal friction angle decreases gently. The pore size distribution (PSD) converted from the T2 curve is constituted of two different peaks, corresponding to micro-pores with diameters from 0.1 to 10 µm and macro-pores with diameters from 10 to 1,000 µm. Under the AGF impact, the expansion in macro-pores and shrinkage in micro-pores simultaneously exist in the specimen, which was verified from a visualized perspective by T2-weighted images. The frost heaving damage on shear strength is attributed to the microstructural disturbance caused by the presence of large-scale pores and uneven deformations in GRS, which is subjected to the AGF impact under an extremely low temperature.

3D printed super-anti-freezing self-adhesive human-machine interface

A 3D printed adhesive and conductive hydrogel with super-anti-freezing property is reported. This hydrogel exhibits excellent stretchability (elongation up to 3920%), outstanding adhesive behavior (adhesion strength up to 61 kPa), as well as marvelous anti-freezing ability (glass transition temperature as low as −96.3 °C). The present 3D printed hydrogel can be used as a sensor with a broad strain range to monitor human motions, slight physiological changes even at an extremely low temperature of −80 °C. Moreover, the hydrogel based self-adhesive electrodes can adhere to human skin directly to collect electrocardiogram, electro-oculogram and electromyogram signals accurately, promising the hydrogel electrodes to serve as a human-machine interface for controlling synchronized motion of anthropomorphic robots, exemplified by playing the piano. We also show that fingers of extraman can be precisely controlled via the self-adhesive hydrogel electrodes even at extremely low temperature of −80 °C. Therefore, the hydrogel fabricated by 3D printing is supposed to have promising potential applications in wearable devices, human-machine interactions, and intelligent bio-electronics, especially under harsh environmental conditions such as extreme low temperature.

Supramolecular Adhesion at Extremely Low Temperatures: A Combined Experimental and Theoretical Investigation.

Adhesive materials that are resistant to low temperatures have wide applications in daily life, scientific research, and industry. Currently, the overwhelming majority of low-temperature-resistant adhesives are traditional polymer systems. In this study, a new strategy was developed to obtain strong and long-lasting adhesion effects from low-molecular-weight adhesives at low temperatures. The introduction of water molecules and the formation of hydrogen bonds not only triggered supramolecular polymerization but also endowed the water-involved copolymer with low-temperature resistance. The water content of the polymeric supramolecular system played a crucial role in exhibiting adhesion behavior at low temperatures. Good adhesion performance was obtained in extremely low-temperature environments, including liquid nitrogen.

A New Extremely Low Power Temperature Insensitive Electronically Tunable VCII-Based Grounded Capacitance Multiplier

In this brief, a new circuit topology to realize an electronically tunable grounded capacitor multiplier with extremely low power consumption and low supply voltage requirement is investigated. The proposed circuit uses an electronically tunable second generation voltage conveyor (VCII) and a single floating capacitor. Owing to the translinear principle, current gain of VCII is varied through a control current and, as a result, the value of simulated capacitor is also varied. Favorably the obtained gain is temperature insensitive. Both of the required supply voltage and control currents are very low because all transistors are biased in subthreshold region: therefore, electronic tunability is achieved while the power consumption is kept at very low value. In addition, the circuit realization is very simple since only twelve transistors are required. Simulation results, performed at schematic level in 0.18 $\mu \text{m}$ CMOS technology and supply voltage of ±0.3V, are presented. It is shown that a multiplication factor from 1 to 100 is possible while the power consumption varies from 10 nW to 67 nW.

(Invited) Exploiting New Electrolytes and Mechanistic Solvation Kinetics for Extreme Low Temperature Batteries

Improving the extremely low temperature operation of rechargeable batteries is vital to the operation of electronics in extreme environments, where systems capable of high-rate discharge are in short supply. Herein, we demonstrate the holistic design of dual-graphite batteries, which circumvent the sluggish ion desolvation process found in typical lithium-ion batteries during discharge. These batteries were enabled by a novel electrolyte, which simultaneously provided high electrochemical stability and ionic conductivity at low temperature. The dual-graphite cells, when compared to industry-type graphite || LiCoO2 full-cells demonstrated an 11 times increased capacity retention at -60 oC for a 10 C discharge rate, indicative of the superior kinetics of the “dual-ion” storage mechanism. These trends are further supported by GITT and EIS measurements at reduced temperature. This work provides a new design strategy for extreme low-temperature batteries. In addition, the electrolytes developed for dual-ion cells have also been extended to search for other high-capacity, high-rate electrodes, which leads to further improved energy density and stability for both high and extremely low temperatures.

Association between ambient temperature and daily emergency hospitalizations for acute coronary syndrome in Yancheng, China.

Acute coronary syndrome (ACS) is a major public health concern worldwide. Few studies have directly evaluated the associations between ambient temperature and ACS incidence. To explore the association between ambient temperature and ACS emergency hospitalizations in the area of subtropical monsoon climate, data on ACS emergency hospitalizations were collected from two highest-ranking hospitals in the central urban area of Yancheng, China, from January 1, 2013, to December 31, 2018. We applied the time-series method to investigate the potentially lagged and non-linear effects of ambient temperature on ACS using the generalized linear model combined with the distributed lag non-linear model after adjusting for time trend, day of the week, holiday, and relative humidity. We identified a total of 5303 cases of ACS emergency hospitalizations during the study period. The exposure-response curves between ambient temperature and ACS hospitalizations were inverse "J-shaped." The effects of extreme low temperature on ACS hospitalizations occurred on the present day and lasted for 3 days, followed by the harvesting effect. The effects of extreme high temperature occurred on the present day and lasted for 5 days. The cumulative relative risks of ACS were 2.14 [95% confident interval (CI): 1.32 to 3.47] for extremely low temperature and 1.66 (95% CI: 1.33 to 2.06) for extremely high temperature over the lag of 0-5 days, compared with the reference temperature (25.0 °C). Both low and high temperatures were significantly associated with higher risks of emergency hospital admissions for ACS in Yancheng, China.

Exploiting Mechanistic Solvation Kinetics for Dual-Graphite Batteries with High Power Output at Extremely Low Temperature.

Improving the extremely low temperature operation of rechargeable batteries is vital to the operation of electronics in extreme environments, where systems capable of high-rate discharge are in short supply. Herein, we demonstrate the holistic design of dual-graphite batteries, which circumvent the sluggish ion-desolvation process found in typical lithium-ion batteries during discharge. These batteries were enabled by a novel electrolyte, which simultaneously provides high electrochemical stability and ionic conductivity at low temperature. The dual-graphite cells, when compared to industry-type graphite ∥ LiCoO2 full-cells demonstrated an 11 times increased capacity retention at -60 °C for a 10 C discharge rate, indicative of the superior kinetics of the "dual-ion" storage mechanism. These trends are further supported by galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS) measurements at reduced temperature. This work provides a new design strategy for extreme low-temperature batteries.

Exploiting Mechanistic Solvation Kinetics for Dual‐Graphite Batteries with High Power Output at Extremely Low Temperature

AbstractImproving the extremely low temperature operation of rechargeable batteries is vital to the operation of electronics in extreme environments, where systems capable of high‐rate discharge are in short supply. Herein, we demonstrate the holistic design of dual‐graphite batteries, which circumvent the sluggish ion‐desolvation process found in typical lithium‐ion batteries during discharge. These batteries were enabled by a novel electrolyte, which simultaneously provides high electrochemical stability and ionic conductivity at low temperature. The dual‐graphite cells, when compared to industry‐type graphite ∥ LiCoO2 full‐cells demonstrated an 11 times increased capacity retention at −60 °C for a 10 C discharge rate, indicative of the superior kinetics of the “dual‐ion” storage mechanism. These trends are further supported by galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS) measurements at reduced temperature. This work provides a new design strategy for extreme low‐temperature batteries.

Spatio-Temporal Dynamics of Jerky Flow in High-Entropy Alloy at Extremely Low Temperature

Despite a large body of literature, mechanisms contributing to low temperature jerky flow remain controversial. Here, we report a cross over from a smooth at room and liquid nitrogen temperatures to serrated plastic flow at 4.2 K in high-entropy CrMnFeCoNi alloy. We show that the jerky flow results from an interaction between dislocation inertial motion with Lomer-Cottrell locks. The instability is shown to result from a competition between the inertial and viscous time scales characterized by a Deborah number. A dynamical analysis shows that jerky flow is chaotic characterized by a finite correlation dimension and a positive Lyapunov exponent.

The key technologies for radial rib deployable antenna of Chang&amp;rsquo;e-4 relay satellite

The radial rib deployable antenna is critical for Chang’e-4 relay satellite. The antenna can be stowed for launch and precisely deploy on the orbit. The deployment of the mechanism, the on-orbit stability of surface accuracy and the validation under the extreme low temperature are the keys for the success of relay satellite. The distributed spring-driven mechanism for the antenna is firstly proposed in this paper. The spring is released slowly in the deployment. The mechanism is verified in the high and low temperature. Secondly, the material and structure of the antenna are optimised for the high stability of surface accuracy. The surface accuracy of the antenna is analysed under extreme conditions. The maximum thermal distortion is far superior to the requirement. The extremely low-temperature experiments are finally designed for validating the capability of antenna based on the simulation of on-orbit environment. The results show the performance of the antenna is unvarying under the extreme low temperature. The radial rib deployable antenna can satisfy all the requirements on orbit and guarantee the success of the relay mission of Chang’e-4 satellite.

Digital X-Ray Flat Panel Housing for Operation at Extremely Low Temperatures

The paper presents the housing wall structure for the digital X-ray flat panel which can operate in extremely low temperature conditions. A technology of three-dimensional printing is proposed for making the detector housing with heat conductors incorporated in its wall structure.