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Ocean temperature, redox state, circulation, and nutrient levels regulate the marine nitrogen (N) cycle, yet their specific impacts during greenhouse intervals remain poorly understood. Here, we examined the Smithian–Spathian hyperthermal event (∼250.5 Ma) during the Early Triassic greenhouse using stable N isotopes (δ15N) from sedimentary records in the Nanpanjiang Basin and Northern Yangtze Basin of South China. The δ15N profiles in both basins reveal consistent trends that correspond to fluctuations in temperature across the Smithian–Spathian transition. The Smithian hyperthermal interval exhibited low δ15N values (mostly <+2‰), indicating N deficiency and enhanced biological N 2 fixation. Bacterial blooms and the release of the potent greenhouse gas N 2 O, enhanced by high temperatures, may have triggered positive feedback mechanisms that sustained the warming and contributed to the late Smithian extinction. During subsequent cooling across the Smithian–Spathian transition, δ15N increased to a range of +3‰ to +7‰, likely reflecting signals of partial denitrification based on reconstruction of the NO 3 − inventory associated with oceanic cooling and oxygenation. The prevailing increases in sedimentary TOC/TN ratios signify heightened deamination (removal of amino groups) and N recycling across the Smithian–Spathian boundary. This transition is likely attributed to cooling-driven amelioration of seawater stratification and anoxia from the Smithian to the Spathian, which resulted in increased nitrate availability in the photic zone. Eukaryotic algae thrived while prokaryotes declined during the Spathian, evidenced by elevated δ15N and Δ13C carb-org (the difference between carbonate and organic carbon isotopes). The proliferation of eukaryotic algae had a positive impact on environmental conditions and facilitated biotic recovery due to more efficient burial of organic particles. A notable latitudinal gradient in the N cycle response was observed, with low-latitude regions showing a more pronounced response to cooling compared to mid-latitude areas. This significant gradient may suggest that the rapid recovery of nutrient cycles, despite relatively small decline in high temperature, was a key factor in the amelioration of climate and recovery of life in low latitudes. These findings highlight that the marine N cycle is highly sensitive to temperature changes, particularly in low-latitude regions, and that changes in N cycle under high-temperature conditions may be a critical life-limiting factor. [ABSTRACT FROM AUTHOR]

A new algorithm is proposed to estimate the cooling amplitude over North China induced by each Ural blocking event. Taking full account of potential transient temperature rises during the cooling process and the lag time of cooling relative to the blocking, this algorithm provides more detailed analysis which should not be possible by using former methods. The amplitude of the Ural blocking-related cooling events is found to have a broad distribution. Further, although most Ural blocking events lead to severe cold surges over North China, the number of Ural blocking events that do not induce significant cooling over North China cannot be ignored. The possible reasons for the wide range in cooling amplitude are explored in terms of the lifetimes and geographical centers of the blocking highs, the circulation patterns preceding the onset of the cooling events, and the snowfall associated with cooling events. Larger amplitude cooling events occur in Ural blocking highs that have longer lifetimes and northwestward displacements of their geographical centers. The northward displacement of a Ural blocking center favors the advection of extremely cold air from the Arctic regions, which accumulates in West Siberia and subsequently gives rise to the most severe cold surges over North China. The lack of activities of cold surges before the blocking-related cooling events not only amplifies the cooling amplitude directly, but also increases the occurrence probabilities of snowfalls through its modulation on the local specific humidity. The increased albedo and subsequent snow-melt induced cooling further amplify the cooling amplitude. [ABSTRACT FROM AUTHOR]

This paper proposes a temperature-adaptive radiative cooling (TARC) coating with simple preparation, cost effectiveness, and large-scale application based on a thermochromic powder. To determine the energy efficiency of the proposed TARC coating, the heat transfer on the surface of the TARC coating was analyzed. Then, a typical two-story residential building with a roof area of 258.43 m2 was modeled using EnergyPlus. Finally, the energy-saving potential and carbon emission reduction resulting from the application of the proposed TARC roof in buildings under different climates in China were discussed. The results showed that the average solar reflectivity under visible light wavelengths (0.38–0.78 μm) decreases from 0.71 to 0.37 when the TARC coating changes from cooling mode to heating mode. Furthermore, energy consumption can be reduced by approximately 17.8–43.0 MJ/m2 and 2.0–32.6 MJ/m2 for buildings with TARC roofs compared to those with asphalt shingle roofs and passive daytime radiative cooling (PDRC) roofs, respectively. This also leads to reductions in carbon emissions of 9.4–38.0 kgCO2/m2 and 1.0–28.9 kgCO2/m2 for the buildings located in the selected cities. To enhance building energy efficiency, TARC roofs and PDRC roofs are more suitable for use on buildings located in zones with high heating demands and high cooling demands, respectively. [ABSTRACT FROM AUTHOR]

In this study, the tallest cooling tower (228 m) completed construction in the world in northwest China was chosen to investigate wind-induced failure mechanism of superlarge cooling towers under tornado. A multiscale finite-element model of the structure was established based on the layered shell element method, and a wind tunnel pressure test was carried out using the tornado simulator. Wind pressure distribution characteristics on inner and outer surfaces of the cooling tower under tornado were analyzed. Moreover, characteristics of the whole wind-induced collapse process of the cooling tower under tornado were studied by combining incremental dynamic analytical method, and the collapse mechanism of a superlarge cooling tower under tornado was extracted. Finally, the failure criterion of the structure under tornado based on the variation rate of the torsion angle was proposed. Results demonstrated that wind pressure showed a circumferential even distribution pattern on the surface of the superlarge cooling tower under tornado, and it generally presented negative pressures. When the cooling tower is located at the tornado vortex core, it is the most dangerous and vulnerable to collapse. Under tornado effects, the cooling tower presented bypassing suction and torsional collapse attitudes from inside to outside. The cooling tower element is designed to improve the antitornado bearing capacity by developing a membrane mechanism. The cooling tower collapsed and failed when the torsion angle failure index φ>0.25. [ABSTRACT FROM AUTHOR]

Analysis of tectonothermal history of the Yanchang Formation in the western Weibei Uplift and in the northwestern Weihe Basin can reconstruct the cooling history of the southwest most remained Upper Triassic source rock of the North China Plate. Apatite fission-track (AFT) and (U-Th-Sm)/He (AHe) analysis were used to recover the cooling and uplift history of the Upper Triassic here. Ten sandstones from the Middle-Upper Triassic strata yield AFT ages between 179.8 ± 7.4 and 127.6 ± 8.1 Ma. AHe ages of two sandstones have the value of 37.7 ± 2.3–131.1 ± 8.1 and 45.7 ± 2.8–83.5 ± 5.2 Ma. Time-temperature modeling results showed that tectonothermal history of the Yanchang Formation was initially different in time-space relationships but then became almost identical through time followed by different cooling rate. Modeling results of the Triassic strata in the Qianyang area and the Yaojiagou area revealed three different uplift-cooling stages commencing in the Late Jurassic at ∼165 Ma and in Early Cretaceous at ∼110 Ma, respectively, both followed by first similar cooling histories to the Early Miocene at ∼20–23 Ma and then different since the Late Miocene. Uplift-cooling rate since the Late Miocene at ∼8 Ma were different between the Western Weibei Uplift and the Northwestern Weihe Basin. The timing, cooling-uplift rates of the Yaojiagou area, which was mainly controlled by movements related to the Liupanshan Mountains, the Qinling Orogens and the Weibei Uplift, had the earliest onset of uplift-cooling for the Upper Triassic series compared to other regions within the Weibei Uplift. Cooling paths for the Upper Triassic series became uniform regionally in the Early Cretaceous marking a key time for the tectonothermal evolutionary history of Upper Triassic series in the southwestern North China Plate. [ABSTRACT FROM AUTHOR]

Passive daytime radiative cooling (PDRC) is a promising strategy to realize surface cooling of objects without any external energy consumption. While such materials typically exhibit dazzling white appearances, developing pleasingly looking colored radiative cooling materials is greatly significant but remains an arduous challenge. Herein, self-standing, flexible colored films available on both sides are prepared by using a facile and scalable strategy. The films are asymmetrically designed. One side is SiO2-filled porous structure with highly reflective pigment distributed that can selectively reflect solar light to generate specific color, and the other side is hierarchically porous three-phase composite with less SiO2, which maximizes the solar reflection. The breathable film achieves a relatively high near infrared reflectance on the colored side (up to 89%), and a broadband solar reflectance on the reverse side. Moreover, both sides exhibit extremely high mid-infrared emissivity (98%) allowing significant radiative heat loss. With the diverse but efficient reflectance and emittance, different sides of three colored films yield temperature drops ranging from 2.0 to 11.1 °C during daytime. Building energy simulation indicates that 655 MJm-2 energy can be saved over the whole summer if the dual-sided available colored film is deployed in China. [ABSTRACT FROM AUTHOR]

The map of radiative cooling potential shows that the radiative cooling power can reach up to 100 W/m2 for its application in different climatic zones. However, the effect of building deployment on the city-scale application of radiative cooling is generally ignored in majority of existing studies, which overestimates the cooling benefit. This paper investigates the cooling benefit of implementing radiative cooling on a city-scale by considering building deployment. To determine the effect of building deployment on the radiative cooling potential, the city of Xi'an in China is modeled using COMSOL and verified with real weather data. Then, the thermal response of buildings with radiative cooling envelopes is discussed in detail. Finally, carbon emission reduction is derived at the city-scale by applying radiative cooling considering building deployment. The results show that the estimated radiative cooling power is approximately decreased by 14.7% for the ideal broadband surface and 47.1% for the ideal selective surface on the selected day by considering building deployment on a city-scale. Furthermore, carbon emission reductions of 0.52 gCO 2 /(m2⋅h) and 0.16 gCO 2 /(m2⋅h) can be achieved from the roof and walls on the selected day by applying radiative cooling material on both the roof and walls. This study can provide guiding significance for the large-scale application of radiative cooling in cities. [ABSTRACT FROM AUTHOR]

Irrigation over the North China Plain (NCP) has been demonstrated to lower temperature by altering the surface energy budget. During past decades, the concurrence of irrigated area variation and reduced irrigation intensity prompted our investigation into whether there has been a temporal change in irrigation cooling effect over the NCP, which is largely unknown. Using historical observations in 1979–2018, we detect a shift in the cooling effect occurring around 1995, when the expansion of irrigated area was going to slow down and water‐conserving irrigation technology was boomingly introduced. After this time, the accelerated process of cooling effect (−0.0045°C year−1) switches to a decelerated one (0.0089°C year−1). Regional climate simulations also show a pronounced slowdown in irrigation‐induced cooling with the rate of 0.0081°C year−1. The irrigation‐induced cooling is expected to be weaker with the persistent reduction in agricultural water use and contribute to a more rapid warming. Plain Language Summary: The North China Plain is the largest irrigated area in China. However, the irrigated agriculture situation in this fertile plain has been going through moderated expansion of irrigated area and reduced irrigation intensity. The variations in irrigation‐induced cooling effect along with this irrigation development were thus investigated based on in situ observations and model simulations. The combined analysis clearly supports a shift from enhancement to alleviation in cooling effect during past decades. The slowdown of irrigation feedback is therefore likely to enable more rapid warming in the future. Key Points: The local cooling effect of irrigation during past decades is evaluated in observations and model simulationsOver the North China Plain, the irrigation‐induced cooling effect has decreased since the mid‐1990sPersistent changes in irrigation water use cannot be overlooked in climate attribution studies [ABSTRACT FROM AUTHOR]

Based on the daily minimum air temperature (Tmin) data and the daily precipitation data from the NCC/CMA combined with the NCEP/DOE reanalysis data, the intraseasonal features and circulations of the winter cold precipitation events (CPEs) in southern China under the influence of strong Madden–Julian oscillation (MJO) were explored. The results show that: (1) Winter temperatures in southern China are characterized by intraseasonal oscillations (ISOs) of 10–30-d and 30–60-d, with six CPEs under strong MJO all occurring during these two intraseasonal scales in cooling phases. The invasion of cold air coupled with the availability of appropriate moisture conditions in southern China is more conducive to the CPEs. (2) A cyclone and anticyclone lying to the east of the Ural Mountains and the northwest of Lake Baikal at 925-hPa gradually move southeastward. The merging of the low-frequency (LF) blocking highs over the Ural Mountains and the North Pacific Ocean at 500-hPa leads to the contraction and southward movement of the LF cold vortex. The following anomalous northerly winds steer the cold air towards southern China. The cold advection is the dominant term in the cooling process, while the adiabatic cooling accompanied with ascending motion is also beneficial to the cooling process. (3) MJO has some effect on the LF blocking highs and the cold vortex in the mid-high latitudes and induces the CPEs over southern China. The joint effect of mid-high and low latitudes on the 30–60-d intraseasonal oscillation scale can have a significant impact on the cooling and precipitation processes of CPEs. [ABSTRACT FROM AUTHOR]

• Mapped PDRC possible cooling energy saving (PCES) across Europe. • Plotted weather data maps to understand the distribution of PCES. • Ranked the PCES for EU countries with and without considering population. • Compared the performance of PDRC for cities in Europe and China at the same latitudes. Passive Daytime Radiative Cooling is a promising technology to reduce surface temperatures below ambient levels even under direct sunlight, potentially helping Europe counteract increasing cooling demands due to frequent heatwaves. This research focuses on mapping possible cooling energy saving of PDRC across Europe utilizing a wavelength-dependent PDRC model, taking into account temperature, total column water vapor, and cloud cover. Moreover, a comparison of cities at analogous latitudes in Europe and China is undertaken. Our results reveal that regions around the Mediterranean Sea have the highest cooling potential, exceeding 180 kWh/m2 annually. For the conditions with and without considering the population, PDRC exhibits the highest possible cooling energy saving in Malta. Besides, possible cooling energy saving of PDRC in Europe decreases from south to north, reaching its lowest in Iceland. However, the northern European regions typically experience summer temperatures below 18 °C. Therefore, northern European regions present limited suitability for PDRC. Notably, while cities at equivalent latitudes in Europe and China exhibit similar annual cooling potentials, the harsh winter conditions in northern China diminish the practicality of PDRC. Thus, European cities demonstrate a more favorable environment for PDRC implementation than their Chinese counterparts at matching latitudes. [ABSTRACT FROM AUTHOR]

Reactivation of the Qinling Orogen since the Late Jurassic has been controlled by the combined effects of the convergence between the South and North China blocks, the subduction of the Pacific Plate, and the northeastward expansion of the Tibetan Plateau. In this study, we present new apatite (U–Th)/He ages from a vertical transect in the Fenghuang Shan located in the North Daba Mountains, where rapid cooling at ∼95-90 Ma is identified. Inverse thermal history modeling results reveal another pulse of accelerated exhumation at ∼50 Ma. In addition, we analyzed longitudinal profiles of rivers draining the northern flank of the Fenghuang Shan and identified knickpoints that break channels into gentle upstream and steep downstream segments. We deduce that these knickpoints were initiated by an increase in the mountain-bounding fault throw, based on nearly constant chi values (an integral to the upstream drainage area distribution) and a reliance of knickpoints' retreat distances on catchment areas. Assuming a linear slope exponent and erodibility of 10−6 m0.1/a, we estimated knickpoint ages to be ∼5.7 ± 1.7 Ma. We interpret the Late Cretaceous cooling as a result of lithospheric extensional collapse following the Late Jurassic intra-continental compression between the North and South China blocks. The early Cenozoic exhumation might relate to the active normal faulting, as a far-field response to the west Pacific back-arc extension. The expansion of the NE Tibetan Plateau may have triggered the late Miocene uplift of the mountain range. The multiple episodes of tectonic events in the Fenghuang Shan might correspond to various geodynamic regimes on the tectonic evolution in the Qinling Orogen. • We combined the methods of both apatite U–Th/He and channel long profile analysis. • The U–Th/He age-elevation transect reveals a pulse of rapid cooling at ∼95–90 Ma. • Knickpoints on channels formed as a response to the late Miocene mountain uplift. [ABSTRACT FROM AUTHOR]

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This paper proposes a load transfer optimization (LTO) model involving hot-spot temperature (HST) and top-oil temperature (TOT) limits of transformers. This work aims to address the overload problem and transformer HST and TOT excursions via LTO. First, the equivalent thermal model for the HST and TOT of transformers under external cooling conditions are discussed, and then the corresponding linearized HST and TOT constraints with varied thermal resistances are derived using the discretization method. Moreover, the proposed LTO model is formulated on the reconfigurable topology of high voltage distribution networks (HVDNs) in China. This proposed LTO model can achieve the optimal network reconfiguration scheme subject to temperature limits and system operation constraints, with the least switching operation cost and the maximum margins of reactive power exchange between HVDNs and transmission systems. Finally, the effectiveness of the proposed LTO model is validated by the modified IEEE-14 node system and the practical HVDNs in China. [ABSTRACT FROM AUTHOR]

There have been several cases of large cooling towers being damaged by wind in history. A typhoon has the characteristics of a strong wind field energy and large shear wind speed. This paper simulates the entire collapse process of large hyperbolic cooling towers by the action of typhoons and refines the typhoon-induced failure mechanism for cooling towers. Firstly, based on WRF-CFD wind field downscaling technology, a fine simulation of the near-ground multiscale wind field produced by China's strongest typhoon "Typhoon Rammasun" is performed to extract effective three-dimensional (3D) typhoon load input parameters. Then, by loading the obtained 3D wind load on the finite element model, a pseudo-dynamic analysis of the world's tallest cooling tower "Luan Cooling Tower" is performed based on LS-DYNA explicit dynamic analysis, and the typhoon-induced collapse process is simulated. Finally, the stress distribution and distortions of the tower and the response time history of key units are compared and analyzed to determine the collapse mechanism. The process of collapse begins with large deformation of the windward surface of the tower throat, which shows folds in the range of 62° on both sides. Eventually, collapse occurs due to uncoordinated deformation. The collapse mechanism can be divided into a bending arch mechanism and a suspension wire mechanism. [ABSTRACT FROM AUTHOR]

High-resolution stalagmite δ18O records, representing Asian summer monsoon (ASM) intensity, were reconstructed from Wulu and Xiao caves, southwestern China, over Chinese Interstadials (CIS) 25 and 22. A most prominent feature of these stalagmite records is a persistent ASM strengthening throughout the entire event, different from a gradual cooling in corresponding events at Greenland and Antarctica. It implicates that the cooling in the Southern Hemisphere may intensify the ASM circulation through increased cross-equatorial flow, which overwhelms the northern high-latitude impact. Combined with previous published records over the past two interglacial-glacial cycles, diverse trends of CIS events generally match with changes in North Hemisphere summer insolation (NHSI). Accordingly, three modes of CIS ASM variability can be observed, i.e., ASM strengthening when NHSI increases, weakening when NHSI decreases, and a relatively stable ASM during NHSI peak. We argue that NHSI variability or interhemispheric gradient could change the strength of cross-equatorial flow, and in turn, alter the landward transport of monsoonal moisture. The mean isotopic composition of moisture, inherited by stalagmite δ18O signal especially in southern China, is likely a reflection of energy balance between hemispheres. [ABSTRACT FROM AUTHOR]

The design of the China Fusion Engineering Test Reactor (CFETR) device is one of the main tasks in the next stage of research on fusion energy in China. The CFETR divertor is a key in-vessel plasma-facing component, which will suffer from sputtering erosion and exfoliation caused by intense plasma bombardment, severe heat fluxes, and neutron irradiation. Due to neutron activation of in-vessel components, remote handling (RH) technology has been considered as one of the essential issues of the CFETR divertor. In this article, a new concept of an integral hybrid divertor blanket for the CFETR is proposed, which is feasible for installation and disassembly in CFETR vacuum vessel by RH. Dome is an important part of the CFETR divertor, which comprises 80 modules, and each module is composed of flat-type plasma-facing units (PFUs), steel supports (SSs), and RH compatible structures. Every Dome module is connected to the CFETR blanket by RH compatible structures. This article mainly carries out the conceptual design of Dome (option), degree of freedom (DOF) analysis, stability analysis, RH process planning, and flow field analysis of cooling scheme, which will provide a solid foundation for its subsequent thermal-hydraulic analysis. [ABSTRACT FROM AUTHOR]

The increasing application of floor heating technology promotes the development of floor radiant cooling technology (abbreviated as FRC technology). Many office buildings in northern China try to use FRC technology to cool in summer, but thermal comfort is the key problem restricting the promotion of this technology. The thermal comfort problems of an office room with floor radiant cooling were studied in this paper by the methods of numerical simulation, control variable, and data fitting, and the experimental results were verified in multiple ways. It was found that, for an office room using floor radiant cooling, the effect of the floor surface temperature on thermal comfort was about 16%, while the effect of indoor air temperature was about 84%, and relative humidity had little effect on thermal comfort. A simplified thermal comfort calculation model was proposed, which could be used as an indicator to adjust the floor surface and indoor air temperature, or could be used to calculate the PMV-PPD value. The findings have guiding significance for the design and control of FRC technology. [ABSTRACT FROM AUTHOR]

Bifacial photovoltaic (bPV) technologies have been garnering increasing attention in recent years due to their ability to generate more power than conventional PV systems. Passive radiative cooling through spectrally selective absorption/emission is considered one of the most practical and cost-effective solutions for the thermal management of bPV modules. In this study, a full-spectrum radiative cooling (FRC) strategy was proposed to maximize the thermal and electrical performance of bPV modules by enhancing above-bandgap absorption, sub-bandgap reflection, and thermal radiation. A multi-physics model was established to characterize bPV performance, enabling analysis of the module's spectral and thermal responses to full-spectrum light under dynamic weather conditions. The proposed model was validated through outdoor experiments with a commercial bPV module, demonstrating good prediction accuracy. To quantify the radiative cooling effect of the ideal FRC strategy and compare it with the ideal traditional radiative cooling (TRC) strategy, a nationwide simulation analysis was conducted across 32 cities in China. The results indicate that the ideal FRC strategy can achieve an annual average temperature reduction of 2.3–4.4 °C and an additional power gain of 7.3%–8.4% for commercial bPV modules. In comparison, the ideal TRC strategy can only achieve an annual average temperature reduction of 1.1–2.2 °C and an additional power gain of 0.38%–0.89%. Results from correlation analysis and sensitivity analysis show that among environmental parameters, wind speed has the most significant positive effect on lowering module temperature, while precipitable water vapor has a relatively small negative impact. Overall, this research demonstrates that the FRC strategy holds great potential for reducing temperature and boosting power output in PV devices, paving the way for promoting the development of sustainable and efficient PV systems. • A full-spectrum radiative cooling strategy was proposed to enhance bPV performance. • A multi-physics model was established allowing for response to full-spectrum light. • Nationwide analysis was conducted in China to quantify radiative cooling effects. • Annual module power output can be increased by 7.3%–8.4% with the proposed strategy. • Wind speed plays the most significant positive effect on reducing module temperature. [ABSTRACT FROM AUTHOR]

In saline lakes, the paleoenvironmental interpretation of long-chain alkenones (LCAs) is difficult due to the inputs of Isochrysidales Group 2i, which are ice-related bloomers. Here, we perform detailed analysis of LCAs and long-chain alkenoates in sediment cores from Lake Daihai in north China. During the late Holocene, alkenone-inferred temperatures and the Group 2i species abundance indicate a long-term warming trend in cold seasons (winter and early spring), possibly driven by regional insolation and by atmospheric CO 2 concentrations. Notably, our records indicate cold climate conditions during the period of 4.3–3.0 cal ka BP, possibly linked to the abrupt expansion of Arctic winter sea ice in a given of low insolation and atmospheric CO 2 concentration conditions. The abrupt cooling may have led to the collapse of the East Aian Summer Monsoon (EASM) and the deterioration of the ecosystems in northern China during the middle to late Holocene transition, and thus likely accounted for the nearly synchronous Chinese Neolithic cultural collapses. • C 36 OEt/C 37 Me ratio is a reliable indicator of March–June warming rate. • Late Holocene cold season warming trend controlled by insolation and CO 2. • The ice-related Group 2i species rapidly increased at 4.3–3.0 cal ka BP. • Abrupt cooling at 4.3–3.0 cal ka BP linked to Arctic winter sea-ice expansion. • The cold-dry and unstable climate led to cultural interruption at 4.3–4.0 cal ka BP. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) wall is expected to match the building type and its climate region effectively. In order to meet the space cooling and heating of residential buildings in hot summer and cold winter regions in China, a new active casing pipe macro-encapsulated PCM wall is proposed, in which the cold storage and heat storage PCMs are sealed between the inner pipe and outer pipe with no leakage. To obtain the optimal structure parameters and better thermal performance of the PCM wall, the mathematical model of the PCM wall is established and validated by experiment, and the effects of PCM filling pattern, structural parameter of casing pipe, water temperature in inner pipe and indoor setting temperature are simulated and analyzed. The results show that the optimal PCM filling pattern is to fill the cold storage PCM and heat storage PCM in the gap between the inner pipe and outer pipe separately; the optimal PCM filling thickness is 13 mm; the optimal structural parameters are inner pipe diameter of 20 mm and casing pipe centre spacing of 61 mm. The water temperature in the inner pipe and PCM energy storage/release time reasonably match the indoor setting temperature. Under the optimal operating conditions, the average PCM wall surface temperatures of 20.5 and 26.8 ℃ and the PCM wall surface heat fluxes of 45.9 and 57.2 W/m2 can be obtained in summer and winter conditions, respectively. The research provides an optimized casing pipe macro-encapsulated PCM wall system that can reliably and efficiently meet both the space heating and cooling demands of residential buildings in hot summer and cold winter regions in China. • A new active casing pipe macro-encapsulated PCM wall with two PCMs for cold and heat storage was proposed. • The physical, mathematical and numerical models of the PCM wall were established and validated. • The effect of different parameters on PCM wall thermal performances was simulated and analyzed. • The optimal parameters of the PCM wall and matching schemes of water and indoor setting temperature were determined. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Yuku ore field shows prolonged post-mineralization cooling varying from 158 to 35 Ma. • The Yuku ore field underwent rapid cooling at ca. 132–125 Ma and multiple various degrees of cooling after 125 Ma. • The un-exhumated areas around the Yuku pluton are favorable sites for Mo prospecting. Molybdenum (Mo) is an important globally strategic metal and mostly occurs as molybdenite (MoS 2) in diverse Mo deposits. The Yuku ore field includes multiple porphyry-skarn Mo deposits and forms a significant world-class Mo cluster in the Qinling molybdenum belt, central China. Previous studies on the ore field were largely related to its genesis, and did not highlight the post-mineralization modifications that are important to formulate prospecting strategies. The exhumation and preservation processes of the ore field through multiple tectonic events also remain poorly understood. Here, we conducted multi-method apatite U-Pb, fission-track and (U-Th)/He and zircon (U-Th)/He medium- to low-temperature thermochronology and related thermal history modelling on granitoids from the ore-hosting Shibaogou and Yuku plutons in the Yuku ore field, and integrated published studies to unravel the post-mineralization exhumation and preservation of Mo deposits. The newly determined apatite U-Pb (158.3–104.9 Ma), zircon (U-Th)/He (158.2–115.0 Ma), apatite fission-track (90.8–63.1 Ma), and apatite (U-Th)/He (67.8–35.3 Ma) ages in this study document multiple cooling pulses during post-magma emplacement. The low-temperature thermochronological ages of 158.2–35.3 Ma also record the post-mineralization cooling and exhumation history. The thermal history modelling indicates an Early Cretaceous (132–125 Ma) rapid cooling pulse, two enhanced (or accelerated) cooling pulses at ca. 125–59 Ma and post-10 Ma, together with a slow cooling or reheating pulse at ca. 59–10 Ma in the Yuku ore field. The Early Cretaceous rapid cooling is related to the coeval collisional tectonics of the East Qinling Orogen. The enhanced cooling at ca. 125–59 Ma is triggered by the post-collisional assembly of the North China and Yangtze Blocks, the subduction of Paleo-Pacific Plate, and the sinistral strike-slip motion of the nearby Tan-Lu Fault Zone. The slow cooling during ca. 59–10 Ma and the post-10 Ma enhanced cooling are correlated with the extensional tectonics derived by the subduction of Pacific Plate and the far-field effects from India-Eurasia collision. The Yuku area underwent lower exhumation in comparison to the nearby Shibaoguo and Huangbeiling areas in the Yuku ore field, which thus is helpful to the preservation of Mo deposits. The un-exhumated areas within 1.0 km at the inner and outer contact zones between the Yuku pluton and its wall rocks are postulated to be favorable sites for Mo prospecting. In addition, the un-exhumated areas surrounding other Late Mesozoic plutons in the Luanchuan region are also suggested to have high potential for Mo exploration. [ABSTRACT FROM AUTHOR]

The Late Mesozoic tectono-thermal evolution and geodynamic setting of the Great Xing'an Range (GXR), particularly in the south margin, are still ambiguous. In this study, we present original low-temperature thermochronological data of six granitoid samples collected from Maanzi pluton in the south margin of the GXR. The apatite and zircon (U-Th)/He ages vary of 70.8 ± 4.3–119.0 ± 7.0 Ma and 120.0 ± 7.1–146.7 ± 8.7 Ma, respectively. Further numerical inverse modeling results reveal that the granitoid plutons experienced a rapid cooling and exhumation stage during Early Cretaceous with a rate of ∼5.0–6.0 °C/Ma and ∼0.14–0.17 mm/yr, respectively, including the western minor pluton emplaced during Early Permian and the major pluton crystallized in latest Jurassic, corresponding to the extensional tectonics in NE China. The rapid exhumation processes in the south margin of the GXR during the Early Cretaceous could be related to both the rollback of Paleo-Pacific oceanic plate and the collapse of thickened crust in the Mongol-Okhotsk Orogen. [ABSTRACT FROM AUTHOR]

In this paper, a new decadal resolution stalagmite δ18O record covering 10.4–6.5 ka BP from Kulishu cave in Beijing, north China is presented in combination with the published stalagmite δ18O record covering 10.4–14.0 ka BP in the same cave. Five significant monsoon collapses were identified around 11.5, 11.0, 10.0, 9.4, and 8.2 ka BP as well as three smaller ones around 10.3, 9.0, and 8.6 ka BP. The weak monsoon episodes around 8.6 and 8.2 ka BP form the two-step structure of the 8.2 ka event. All monsoon collapses, coeval with the cooling in northern high-latitude records, are correlated with Lakes Agassiz-Ojibway outbursts. Thus, our data support the idea of freshwater forcing of abrupt climate anomalies during the early Holocene. Nevertheless, the decreased irradiance together with freshwater outburst may account for the 9.2/9.3 ka event, which is expressed more significantly in low-latitude records. [ABSTRACT FROM AUTHOR]

The mechanisms of abrupt seasonal temperature changes and warming (cooling) hiatuses remain unclear. Clarifying how they respond to various influencing factors is critically important to understanding their mechanisms. In this study, the influencing factors to which the abrupt changes in Tav, Tnav, and Txav were most sensitive followed the order of (AGG and CO2) > SR > WS > AMO > PDO > MEI > AO > AP > RH. Seasonal Tav had the greatest sensitivity to all influencing factors, followed by seasonal Tav and lastly by seasonal Txav. An abrupt temperature change occurred when AGG, AMO, or SR increased continuously to a certain value, when PDO was in a positive phase (warm phase) and increased continuously to a certain value, when MEI changed abruptly, when WS and RH continued to decline for a certain time and reached a certain tendency rate, or when AP continued to decline for a certain time and reached a certain value. During the period before and after the warming (cooling) hiatuses, the temperature at most of the stations only had a significant relationship with a few influencing factors, and the hiatuses in seasonal Tav, Tnav, and Txav were overall most sensitive to changes in WS, followed by changes in RH and lastly by changes in AP. The occurrence of warming (cooling) hiatuses was highly consistent with the variation trend of some influencing factors, which to some extent affected the warming (cooling) hiatuses. Abrupt seasonal temperature changes/warming (cooling) hiatuses are the combined effects of multiple influencing factors. [ABSTRACT FROM AUTHOR]

purpose of this study is to evaluate the factors involved in the early stage of exertional heat stroke (EHS) that are associated with mortality. Methods: In this retrospective, case-control study, patients from 11 tertiary medical centers in China were enrolled from January 1, 2012, to December 31, 2019. Demographic information, underlying diseases, ambient temperature, and relative humidity, clinical manifestations, initial body temperature, time from onset to diagnosis of EHS (including suspected), and the duration of body temperature > 38°C of all enrolled patients were recorded. The occurrence of organ dysfunction within 72 h was evaluated, and in-hospital deaths were recorded. The patients were subsequently divided into a survival group and a non-survival group. The "case" refers to patients in the non-survival group, while the "control" refers to patients without death. Results: Of the 214 hospitalized patients with EHS, 183 survived and 31 died, and the overall mortality was 14.49% (31/214). A binary logistic regression showed that only the duration of body temperature > 38°C (OR 1.80, 95% CI 1.34– 2.42) and the number of organs damaged within 72 h of onset (OR 6.54, 95% CI 2.31– 18.56) were statistically significant in terms of risk of death in hospital (p < 0.05). A goodness of fit test produced a p-value of 0.76. According to receiver operating characteristic curve (ROC) analysis, the areas under the curve (AUC) were 0.989 (95% CI 0.978– 1.000; p < 0.05) and 0.936 (95% CI 0.896– 0.976; p < 0.05). Conclusion: Of the various factors involved in the early stage of the disease, the duration of high body temperature and the number of organs damaged within 72 h of onset were independent risk factors and predictors associated with death. [ABSTRACT FROM AUTHOR]

The viability of fan and natural ventilation, combined with evaporative cooling, was investigated using a simulation model and weather data for thirty-seven locations in the world (mostly in China). And the geographical distribution pattern of viable cooling technologies was examined in China. The model used was based on a simplified steady-state heat balance of a greenhouse, and weather data were from corresponding meteorological organizations. The evapotranspiration coefficient used two values of 0.5 and 1.0, and ventilation rates for natural ventilation were based on two empirically constructed equations. The results suggested that the viability of various cooling technologies depended largely on local weather, although evapotranspiration coefficient and ventilation characteristics of natural ventilation also played important roles. Some locations were sensitive to evapotranspiration coefficient and ventilation rate while some were not. The locations which were not sensitive to evapotranspiration coefficient and ventilation rate could choose the most economical technology to meet the cooling minimum, but these locations which were sensitive required evaporative cooling and/or forced ventilation. A detailed examination of the geographical pattern of viable cooling technologies was conducted for China. The results suggest that high altitude general provides a cooling advantage [ABSTRACT FROM AUTHOR]

Ground source heat pumps (GSHPs) are one of the renewable energy technologies with features of high efficiency, energy saving, economic feasibility and environmental protection. In China, GSHPs have been widely used for building heating and cooling in recent years, and have shown great potential for future energy development. This paper summarizes the classification, development history, and use status of shallow GSHPs. Several typical engineering cases of GSHP technology are also specified and analyzed. Finally, promising development trends and some advanced technologies are illustrated. [ABSTRACT FROM AUTHOR]

Urban climates could significantly impact building energy consumption. This study aimed to investigate the impact of urban-rural disparities in temperature and humidity on building cooling and heating demand in multiple cities. Fixed stations were established using temperature/humidity loggers deployed at 17 pairs of urban and rural sites in 15 cities in eastern China. The study analyzed the differences in air temperature (Δ T a), relative humidity (Δ RH), and dew-point temperature (Δ T dew) between the urban and rural sites. These climatic data were then used as inputs for the energy simulation of a residential building. The following results were revealed: (1) Δ T a was consistently higher at night than during the day. In comparison with the rural reference sites, the RH values at all urban sites were lower; however, some urban sites displayed lower T dew , while others exhibited higher T dew. (2) Regarding annual total energy demands, urban buildings exhibited variable changes in energy components compared to rural buildings. Sensible cooling demands increased by 10 %–36 %, while heating demands decreased by 9 %–30 %. Latent cooling demands ranged from a decrease of 12 % to an increase of 17 %. As a result, overall changes in annual total energy demands (cooling + heating) were relatively small, ranging from −2 % to +7 %. (3) Regarding daily total energy demands, a 1 °C increase in Δ T a led to a 12.1 % increase in sensible cooling demand and an 8 % decrease in heating demand. At the same time, a 1 °C variation in Δ T dew corresponded to a 14.6 % change in latent cooling demand. (4) Regarding the daily peak load, modifications in local temperature and humidity in urban areas had a more pronounced impact on daily peak heating loads than on daily peak cooling loads. This study could enhance our understanding of how urban local climates affect building cooling and heating energy demands. • Climatic observations from 17 pairs of urban and rural sites in 15 cities were used. • Not only the impact of Δ T but also the rarely discussed humidity were analyzed. • UHI led to increases (decreases) in building's sensible cooling (heating) demand. • Changes in latent cooling demand is positively linearly correlated with Δ T dew. • Impact on daily peak heating loads is more significant than on peak cooling loads. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cross-linked silica-hybridized cellulose aerogels are facilely prepared. • The aerogels combine thermal insulation and radiative cooling in one design. • The aerogels with enhanced spectral selectivity show durable cooling performance. • A year-round total energy saving of 13.87 kW m−2 in China can be achieved. Passive radiative cooling (PRC) is a promising carbon reduction technology that radiates heat into the universe through atmospheric transparency window (ATW) to cool objects below ambient temperature with zero energy consumption. However, so far the cooling efficiencies of most PRC designs are inevitably restrained by inadequate optical properties and parasitic heat gains from ambient air. These defects are overcome by developing aerogel coolers with functional integration of low absorption of solar irradiance, strong mid-infrared emittance, and high thermal insulation in one design. In particular, cross-linked silica-hybridized cellulose acetate is exploited to construct robust aerogels with well-arranged nano/micro porous structures, representing a solar reflectance up to ∼96 % and an ATW emissivity of ∼97 %. Such aerogels can realize a subambient temperature drop of ∼9.15 °C during the daytime and maintain their remarkable cooling performance even in cloudy, moist, and windy climates. The aerogel coolers also show excellent anti-aging, self-cleaning, and compression resistance, making them adaptable for long-term cooling applications. The year-round energy consumption simulations demonstrate that an average total energy saving of 13.87 kW m−2 per year can be promisingly achieved in China when the aerogel coolers are integrated on building roofs. This work paves a new way to manufacture more cost-effective and sustainable cooling materials for efficient building energy conservation in the future. [ABSTRACT FROM AUTHOR]

• A novel geopolymer-based inorganic SDRC coating was developed. • The optimized SDRC could retain optical stability up to 1000 ℃ exposure. • A sub-ambient cooling effect of 3.8 ℃ under direct sunlight in Hong Kong was achieved. • The simulation results demonstrated great cooling energy saving potential under different climates in China. Passive sub-ambient daytime radiative cooling (SDRC) is an energy-free method enabling heat dissipation away from buildings or infrastructures to cold outer space (∼3 K). However, although organic coatings (based on polymer matrices) have been proven to be a cost-effective means to achieve the SDRC effect by incorporating various functional fillers, organic coatings may have environmental concerns and aging problems. Herein, an inorganic phosphate activated geopolymer-based (PAGP) SDRC coating was synthesized using nano-silica (SiO 2) particles and barium sulfate (BaSO 4) sheets as the modifiers. The synthesized coating could achieve high infrared emissivity of 0.9634 and solar reflectance of 0.9471, which was also found to exhibit high-temperature resistance and optical stability up to 1000 °C due to its covalently bonded structure and electrically neutral system. The chemical composition, surface morphology, and elemental distribution of the coating were characterized by XRD, FTIR, SEM, BET, and EDS. The evolution of condensed structures and weight loss analysis during the high-temperature treatment was conducted by TGA and XRD to analyze the dehydration process and phase change during the heat process. The outdoor field tests showed a maximum sub-ambient temperature reduction of 3.8 °C by the developed coating without any energy input under direct sunlight in Hong Kong. Furthermore, the energy-saving performance of the PAGP-based SDRC coating is analyzed under different climatic conditions in China with the aid of EnergyPlus. Simulation results demonstrated that the PAGP-based SDRC coating can significantly save the cooling load in all five selected cities, which shows great potential in building energy conservation and carbon emission reduction. [ABSTRACT FROM AUTHOR]

This article proposes a novel optimal sizing method for the energy station in the multienergy system (MES) integrated with data center. First, an overall framework of the energy station, data center, and multienergy loads is constructed to describe the interconnection of energy system and information system. Then, the dynamic voltage frequency scaling (DVFS) technique, the thermal inertia, and the deep coupling relationships of the electricity load, waste heat, cooling load, and workload in the data center are respectively modeled. On this basis, the optimal sizing model of the energy station is established, in which the data center can participate in the integrated demand response by the DVFS technique and thermal inertia. The capacity of energy station and the scheduling schemes of energy devices and servers are optimized simultaneously to coordinate the energy flow and information flow. Based on the quasi-steady-state assumption of thermal balance, the model is simplified to a mixed-integer quadratic program problem, and it is solved by Gurobi. Case studies based on a real-world test system in China illustrate that the integration of data center can be utilized to reduce the total cost of energy station planning in MES. [ABSTRACT FROM AUTHOR]

Nighttime ozone (O3) reserved over the stable boundary layer (SBL) could contribute significantly to surface O3 levels. While many studies have revealed that daytime convective eddies and turbulence induced by nighttime low‐level jets can mix O3‐rich air over the SBL down to the surface, increasing nocturnal surface O3 within the cloud topped boundary layer has rarely been examined. In this study, we used measurements and a single‐column photochemistry model to investigate O3 variations within the nighttime cloud topped boundary layer over the Sichuan Basin, which is the cloudiest region in southwest China. The Santa Barbara Distort Atmospheric Radiative Transfer radiation model was coupled into the single‐column photochemistry model to investigate the nighttime radiative effects of clouds. The results showed that the nocturnal cloud top radiative cooling generated turbulence and enhanced vertical mixing below the cloud top layer. The cloud‐driven turbulent eddies even penetrated through the SBL to the surface. Consequently, it weakened the decoupling of the SBL from the residual layer. O3‐rich air over the SBL was entrained downwards to the surface, decreasing O3 aloft and increasing surface O3 at nighttime. The cloud top radiative cooling rates were enhanced with the increase in the cloud liquid water path. Higher cooling rates produced stronger turbulent transport of O3, leading to higher nocturnal surface O3 levels. The turbulent transport of O3 induced by cloud top radiative cooling is revealed as an important mechanism of vertical transport of O3 within a cloud topped boundary layer, contributing to the maximum nocturnal surface O3, which has great implications for understanding atmospheric O3 variation. Key Points: A mechanism of vertical transport of O3 within a cloud topped boundary layer is revealed using measurements and simulations.The contribution from vertical transport to surface O3 increases with cloud liquid water path, with maximum surface O3 enhancing by 30 ppb at nighttime. [ABSTRACT FROM AUTHOR]

Stochastic cooling of the spectrometer ring (SRing) at the High Intensity Heavy-Ion Accelerator Facility (HIAF) project in China, which is used mainly for experiments with radioactive fragment beams, is applied to speed up the cooling process of a stored ion beam. In this study, both a Faltin traveling wave structure and a novel slot-ring standing wave structure based on a ceramic vacuum chamber are discussed and evaluated for the pickup/kicker of the SRing stochastic cooling system. The slot-ring structure should significantly improve the shunt impedance due to the Cherenkov effect. For the Faltin-type structure, the results for the pickup shunt impedance obtained from simulations and from beam measurements agree well. Good agreement is also found between the simulated and measured results for the pickup shunt impedance of the slot-ring structure. Cooling process simulations using the Fokker–Planck equation based on the shunt impedance results for the Faltin- and slot-ring-type pickups are also presented. [ABSTRACT FROM AUTHOR]

The kelp grouper Epinephelus moara has high economic value and is popular in fisheries and aquaculture in China. In the previous study, we treated the embryos at 16–22 somite stage at 4 °C, −25.7 °C, −140 °C and −196 °C, and successfully obtained surviving embryos in each group. To better understand the molecular changes affected by the low temperatures, we conducted a comparative transcriptome analysis among embryos exposed at 4 °C for 30 min, embryos exposed at −25.7 °C for 30 min and the control group. qPCR assays were conducted for the validation. Signal transduction pathways were highly enriched for the differentially expressed genes. c-Fos , c-Jun , JunD , GADD45 , involved in MAPK signaling pathway, were upregulated when embryos were treated at low temperatures. As immediate early genes, Egr-1a and b , and IER2 , that respond quickly to the environment stress, their expression increased as well. Hsp70 showed similar expression pattern as immediate early genes. Meanwhile, transcription factors Sox , HES , TFIID , muscle movement and protein synthesis-related genes were downregulated. Taken together, our findings suggest that cooling disrupts gene expression patterns in E. moara embryos. The differentially expressed genes may be involved in cellular resistance against low temperatures, possibly through neural activation, apoptosis, proliferation, differentiation, cellular recovery and heat shock regulation. This study also provides transcriptome dataset of E. moara embryos exposed to cold temperatures for future studies focusing on the molecular effects of cryopreservation. Image 1 • Cooling disrupts gene expression patterns in Epinephelus moara embryos. • Genes invovled in MAPK signaling pathway and immediate early genes were upregulated in embryos treated at low temperatures. • Meanwhile, Some transcription factors, muscle movement and protein synthesis-related genes were downregulated. [ABSTRACT FROM AUTHOR]

This study reports Ca-Fe isotope compositions of mineral separates in a set of peridotite xenoliths including ten lherzolites, one harzburgite, and one wehrlite from Hainan Island, south China. Iron isotope compositions show a small variation (<0.15‰ of δ56/54Fe) among olivine (ol), orthopyroxene (opx), and clinopyroxene (cpx). Δ44/40Ca opx-cpx (δ44/40Ca opx -δ44/40Ca cpx) show a large range from 0.00‰ to 1.23‰. Together with data in previous studies, Δ44/40Ca opx-cpx in mantle xenoliths worldwide show a negative correlation with the apparent temperatures, which cannot be explained by equilibrium fractionation. Instead, the observed inter-mineral Ca isotope fractionation between opx and cpx (>2‰) in previous studies should be dominated by disequilibrium sub-solidus Ca redistribution between cpx and opx, which is driven by the changes of mantle temperature and chemical composition in pyroxene. The wehrlite, which was formed by reaction of peridotite with an evolved, silica-undersaturated melt, has δ44/40Ca of 3.22‰ and δ56/54Fe of 0.22‰, significantly heavier than the value of fertile mantle. Such heavy isotope signatures in the wehrlite are best explained by diffusion during the metasomatic melt percolating the refractory mantle. In summary, this study reveals that significant kinetic Ca isotope fractionations could occur in the mantle by inter-mineral Ca diffusion during re-equilibration upon cooling and Ca diffusion from melt into peridotite during melt percolation. [ABSTRACT FROM AUTHOR]

• A non-reciprocal MIR window with pyramidal micro-structures is designed. • The non-reciprocal window allows to radiate heat to outer space while suppressing the incoming heat flux. • A temperature reduction limit of 110 °C is possible under a low-transparency sky. • A temperature reduction of 10 °C can be preserved under an unfavourable weather and surroundings condition. • Use of the non-reciprocal window promises a 45% energy savings for cooling during China's summer, around 180 TWh. Passive radiative cooling has a potential impact on global energy consumption, while it is vulnerable to weather and surroundings, hindering its practical applications. Here, we present a facile pyramidal micro-structure that can be formed on a mid-infrared (MIR) window for achieving non-reciprocal propagation whereby the incoming heat flux from low-transparency atmosphere and/or surrounding high-rise buildings is suppressed without limiting the outgoing radiation from radiative coolers. In an ideal case without solar absorption, convective, and conductive heat losses, a temperature reduction limit of 110 °C is simulated even under a low-transparency sky. For an unfavorable weather and surrounding obstruction condition, the radiative cooler integrated with the non-reciprocal MIR window can still reach a 10 °C temperature reduction, while a standalone radiative cooler fails the sub-ambient cooling. The effects of non-reciprocal MIR windows on China's average temperatures in summer are estimated, roughly corresponding to a 45% energy savings for cooling, around 180 TWh. This universal strategy would remove the bottlenecks of putting passive radiative cooling into practice worldwide even if local weather and surrounding terrain conditions are undesirable. [ABSTRACT FROM AUTHOR]

Late Cenozoic basaltic lavas in eastern and southeastern China commonly display spectacular columnar joints. In four volcanic fields in this region, we have observed and classified five types of colonnade (vertical, inclined, horizontal, fanning upwards, and fanning downwards) that provide information on the cooling regime and emplacement mechanism of the lava flows. In total, we analyzed the geometry and morphology of joints across ten different lava flow areas in the Changle volcanic field (CVF), Luhe volcanic field (LVF), eastern Zhejiang volcanic field (EZVF), and Niutoushan-Linjin Island-Nanding Island volcanic field (NLNVF). Field observations show that columnar-jointed alkaline basalts commonly exhibit narrow and irregular shapes indicating fast cooling. Tholeiites with columnar joints, in contrast, show wide and regular polygons, indicating slower cooling. Vertical columnar joints and other types (horizontal and fanning shaped) have different mature patterns, with the implication that lavas flowed on relatively flat land and in paleo-valleys, respectively. This study suggests a simple qualitative description of different types of colonnade can be made based on their alignment patterns, which represents a direct and easy way to derive solidification processes after lava eruption from colonnaded lavas in outcrop. [ABSTRACT FROM AUTHOR]

The Chinese Fusion Engineering and Testing Reactor (CFETR) has been performed and is in its engineering design stage. Presently, there are two options allowed for the divertors; the helium-cooled stage and water-cooled stage. The water-cooled one has been focused in this article. The configuration of CFETR divertor module was designed. The cassette design scheme and cassette box inner and outer locking systems were introduced, and the locking system was designed to compliant with the remote-handling (RH) requirements. Two divertor RH design options were provided: one is removed through lower port; the other is targets and baffles removed through upper port; supports and cassette were not removed. The other major research was the water cooling channels’ design and its pressure drop calculation. In addition, the fluid, thermal, and mechanical analyses on the outer target were done. Within 10-MW/m2 heat flux, outer target design can ensure that the temperature for all the components works within their temperature limit, and all the components meet the stress design criteria except the copper alloy pipe. The maximum primary stress induced by pressure on the copper alloy pipe appears in the local position between the two monoblocks, which exceeds the design limit. Protection components are need to be added at the gap of the future design optimization to reduce the local stress. After the thermal-hydraulic analysis on water-cooled divertor cassette, the maximum temperature and the maximum stress of cassette meet the requirements. The results of electromagnetic force analysis shows that the deformation on first wall and transition support is less than 0.5 mm, and the maximum stress is also below its tensile strength values. This article summarized the latest achievements in the design and research of CFETR water-cooled diverter in China. All the results will be of great reference for the CFETR divertor optimal design. [ABSTRACT FROM AUTHOR]

This article analyzes the changes that have taken place in Northeast Asia, where the Korean Peninsula is located. As we know, in recent years China's foreign policy has largely changed, and this is primarily due to China's increasing role in the international arena. The article analyzes in detail the evolution of China's policy towards the two states of the Korean Peninsula, stages, changes in relations between North and South Korea. Sudden rapprochement with North Korea during 2018-2020 and a sharp cooling of relations with the Republic of Korea after the deployment of the US missile system THAAD in South Korea. Of course, the sharp escalation of the confrontation with the United States also played a role in the Korean problem regulating and in the process of the Korean Peninsula denuclearization. The article reveals the factors that influence the change in China's foreign policy towards North and South Korea. [ABSTRACT FROM AUTHOR]

The information on downward longwave (LW) radiation is necessary for the design of the passive cooling system of buildings. Because the measured LW radiation data are not available in most locations, few studies have focused on the modeling of LW radiation in China. In this study, empirical models for estimating LW radiation were proposed under all-sky conditions based on the meteorological parameters such as the ambient dry-bulb temperature, water vapor pressure, and relative humidity, which can be classified into four cases: All day, nighttime, and daytimes with and without considering the cloud modification factor. The proposed models performed are well compared with the existing models. The LW radiation datasets for 351 locations of China were developed using the proposed model for all the day based on the typical meteorological year. Moreover, the distribution map of radiative cooling potential in July was created using the proposed model for the nighttime, which can provide a valuable reference for building cooling design. [ABSTRACT FROM AUTHOR]

Summary: Distributed generation (DG) technologies are environmentally friendly and have low operating costs, and thus, distributed generators are widely used for the energy supplies of buildings. Solar energy used for on‐demand heating of buildings is also a mature technology that is environmentally friendly and inexpensive and has a short recycling life cycle. This paper proposes a high proportion of new energy access–combined cooling, heating, and power (HPNE‐CCHP) system composed of a distributed generator and solar energy heat pump system. To obtain the optimum capacity of the HPNE‐CCHP system, nondominated sorting genetic algorithm‐II (NSGA‐II) was used to optimize the system by considering the life cycle cost (LCC) and life cycle pollutant emissions (LCPE) as the objective functions. A mixed integer economic scheduling model (MIESM) was proposed to make the HPNE‐CCHP system operate more economically. Finally, an HPNE‐CCHP system was constructed for a building in Northern China. The simulation results show that an HPNE‐CCHP system with a moderate proportion of new energy is more economical and environmentally friendly than a traditional CCHP system. Building occupants, depending on their desired spending, can select the best capacity configuration on the Pareto frontier. Although pollutant emissions will be reduced as the proportion of new energy increases, this type of configuration is expensive. [ABSTRACT FROM AUTHOR]

We present comprehensive Li-C-Sr isotopic studies on two classic marine carbonate sections (Yangdi and Dongcun) transecting the Late Devonian Frasnian-Famennian (F F) boundary from South China to constrain the causes of the F F mass extinction. Both sections show positive Li and C isotopic excursions in carbonate and unchanged conodont 87Sr/86Sr ratios across the F F boundary. Low Li/Ca and Sr/Ca ratios, but heavy Li isotope composition (δ7Li) of the Dongcun section indicate possible diagenetic alteration on carbonate Li isotopic records. By contrast, the Yangdi section records more primary seawater δ7Li signal, showing a ∼ 2 ‰ positive excursion before the F F boundary, although reconstructed paleo-seawater δ7Li values (from 11.8 ± 1.4‰ to 13.8 ± 1.4‰) are lower than modern times. Combined box model with Monte Carlo simulation demonstrates that low seawater δ7Li requires low riverine δ7Li and small effective Li isotopic fractionation by marine sinks (Δ7Li sw-ms). The latter is likely due to high silicon concentration in the paleo-seawater and rapid formation of clay minerals. Positive δ7Li excursion but invariant 87Sr/86Sr ratios in the seawater are related to attenuated continental weathering (reduced riverine fluxes but increased riverine δ7Li), and enlarged effective Δ7Li sw-ms. Based on the present data we suggest that rapid climate cooling is responsible for the weathering transition and must have exerted significant influence on the marine environment. Global climate cooling weakens seawater stratification while intensifying oceanic circulation and upwelling, resulting in enhanced primary productivity, precipitation of the Kellwasser black shales and a remarkable positive C isotopic excursion in carbonate. Additionally, rapid climate cooling around the F F boundary has significantly threatened the ecological system and finally triggered mass extinction especially for the faunas adapted to warm temperatures. • Positive carbonate Li C isotopic excursions are observed around the F F boundary. • Conodont 87Sr/86Sr ratios are unchanged. • Modeling results indicate attenuated continental weathering. • Rapid climate cooling triggered the F F mass extinction [ABSTRACT FROM AUTHOR]

[Display omitted] • Superamphiphobic-enhanced inorganic coating is designed for durable building cooling. • R solar ∼98% and ε AW ∼98% are achieved to help reduce ∼7℃ at >1400 W/m2 of solar power. • Superamphiphobic surface help avoid >7.5℃ of thermal accumulation by oil pollution. • Over 35% energy consumption in China can be saved as the application of PRC coating. Passive radiative cooling (PRC) is a promising technology to achieve eco-friendly building cooling relying on automatic solar reflection and thermal emission. However, sewage, oil and even dust in actual application often cause irreversible damage of surface optical selectivity required by durable cooling. Herein, ZnAl LDO biomimetic microflowers are fabricated as optically selective substrate following by crosslinking of superamphiphobic (SAP) SiO 2 nanoparticles to obtain inorganic SAP-PRC coating. Openly-porous micro-nano-structure from LDO microflowers imparts the coating excellent solar reflectivity (∼97.58% normalized with BaSO 4) and thermal emissivity (∼98%) as well as efficient resistance for both water (contact angle >158°/slide angle <5°) and oil (contact angle >151°/slide angle <10°). As the result, the coating achieves about 7℃ of cooling effect under (>1400 W/m2) of solar radiation and ∼5℃ lower than the commercial coating. The superamphiphobic surface help SAP-PRC coating avoid over 7.5℃ increase of temperature under >1500 W/m2 after being immersed by oil pollution. It is estimated that the cooling coating can help achieve ∼26% energy saving in hot areas (Haikou in China) throughout a year also considering warming-energy consumption in winter. The synergistic self-cleaning and optical selectivity strategy will effectively promote the commercialization of building PRC materials and further contribute to energy and environment sustainability. [ABSTRACT FROM AUTHOR]

Passive sub-ambient daytime radiative cooling has been demonstrated in previous studies by rigorous spectrum-tailored coolers with high solar reflection and strong thermal emission. In this work, a general strategy to change the relative position between the radiative coolers and the sun was proposed to decrease solar radiation reaching the coolers. In this way, passive sub-ambient daytime radiative cooling was well demonstrated on the basis of two commonly available coolers, coolers A and B. Cooler A was fabricated by attaching a 20 μm-thick polydimethylsiloxane film on a reflective metal substrate, and cooler B was a commercial reflective mirror. A field test was conducted for coolers A and B toward north sky in Hefei (117°E, 32°N), China. Results show that the average temperature drops below ambient temperatures of coolers A and B are 3.2 °C and 7.4 °C, respectively, which indicate that the proposed strategy can achieve passive sub-ambient daytime radiative cooling. Furthermore, the feasibility of the proposed strategy for daytime radiative cooling was also proved using a universal thermal model. This work provides a new insight into passive sub-ambient daytime radiative cooling and opens up a new avenue for common materials to potentially achieve sub-ambient daytime radiative cooling. • A general strategy was proposed to decrease solar radiation reaching the coolers. • The proposed strategy can achieve sub-ambient daytime radiative cooling. • Daytime radiative cooling was demonstrated by commonly available coolers based on proposed strategy. • This work provides a new insight into passive sub-ambient daytime radiative cooling. [ABSTRACT FROM AUTHOR]

Perturbations to the global carbon and sulfur cycles recurred episodically throughout the ~5-Myr-long Early Triassic, in the aftermath of the end-Permian mass extinction, the largest biocrisis in Earth's history. In this study, analyses of carbonate-associated sulfate (CAS) sulfur, CAS oxygen, and pyrite sulfur-isotope ratios in a continental shelf section from the southern Neo-Tethys Ocean (Spiti Valley, India) provide new insights into the Early Triassic marine sulfur cycle. Secular variation in CAS sulfur-isotope values at Spiti is similar to that in South China, suggesting that CAS was a robust recorder of a global seawater sulfate signal. The Spiti CAS and pyrite δ34S profiles show that the highest rates of pyrite burial coincided with cooler sea-surface temperatures. We infer that climatic cooling steepened equator-to-pole temperature gradients, invigorating thermohaline overturning circulation, and enhancing upwelling of nutrients that stimulated marine productivity and organic carbon sinking fluxes. Enhanced productivity fueled and sustained microbial respiration, increased oxygen demand, and, within the southern Neo-Tethys, caused the zone of microbial sulfate reduction to migrate upwards and become more connected to the water column. Microbial sulfate reduction, under these conditions, was no longer limited by organic matter or sulfate availability, leading to burial of more 34S-depleted pyrite and 34S- and 18O-enrichment of the oceanic sulfate pool. This environmental scenario suggests possible environmental stresses related to eutrophication during positive carbon-isotope excursions around the Griesbachian-Dienerian, Dienerian-Smithian, and Smithian-Spathian boundaries. Additionally, the difference between CAS and pyrite sulfur-isotope values, Δ34S CAS-pyr , slowly rose through the Early Triassic, reflecting a slow increase in seawater sulfate concentrations following a minimum close to the Permian-Triassic boundary. [ABSTRACT FROM AUTHOR]

The use of gas cookers with electric ignition systems is widespread in China. It's meaningful to design a small-scale thermoelectric generator (TEG) which converts low-grade heat into high-grade electricity to power the ignition in order to reduce consumption of non-rechargeable dry cells. To provide effective cooling over short periods of time (~15 min) for the intermittent operation of the TEG, this study proposes a closed, flooded and passive cooling system based on the loop-thermosyphon principle. It has higher cooling efficiency compared to air-cooled natural convection, operates automatically without fans or pumps, avoids the startup problem of active cooling and improves the reliability of long-term operation. Firstly, Simulation Driven Design (SSD) approach was employed to optimize the cooling system designed for use with a single thermoelectric generator (TEG) module. Secondly, an experimental bench-test of the TEG used the cooling system with the pipe diameter of 7 mm and the height difference of 50 mm was made, and the results showed that the time periods of output power higher than 1.0 W was 506 s and the output energy was about 0.2 W·h with the output voltage higher than 1.5 V. Finally, a TEG-cooker prototype was built by integrating the TEG and an electricity storage module inside an embedded gas cooker. By testing, it was found that the electricity storage module started charging after the TEG-cooker working for 3 min. The burner turned on at the maximum firepower continued combustion for 15 min, and the electric energy stored in the energy storage module can be used to ignite the TEG-cooker 30 times. Unlabelled Image • A closed and flooded cooling system based on the thermosyphon principle was designed. • SDD approach verified by experiments was employed to optimize the cooling system. • Power generation performance of the TE generator was tested experimentally. • A TEG-cooker prototype paired with an electricity storage module was built. • The TEG-cooker is self-provided power supply and free from disassembling and maintaining. [ABSTRACT FROM AUTHOR]

• The maximum generalized entropy principle is introduced in the evaluation. • The impact of operating strategies on the integrated performance is studied. • Economical, energetic, exergetic and environmental indicators are considered. In order to promote the environmental conservation and energy efficiency, sufficient attention has been paid to biomass gasification-based combined cooling, heating and power (BGBCCHP) systems. Accurate evaluation of BGBCCHP systems is helpful to improving its performance. The maximum generalized entropy principle was introduced to reveal the essential characteristics of BGBCCHP systems. The BGBCCHP system was regarded as an open and evolutionary information network. Annual total cost, annual primary energy consumption, annual carbon dioxide emissions and exergy efficiency were used as evaluation criteria. Reasonable weights were conferred to the criteria so as to make the system stable. Moreover, an evaluation model based on the maximum generalized entropy principle was established to determine the eigenvalues of the BGBCCHP system. Self-organizing feature map network was used to simulate the evaluation model of the BGBCCHP system. A case study based on an office building in Beijing, China, was carried out. Three operating strategies (following the thermal load, following the electric load and following the hybrid electric-thermal load) were considered in the evaluation of the BGBCCHP system. Sensitivity analysis was carried out to investigate the impact of economic and technical parameters on the evaluation results. Results indicated that the evaluation model based on the maximum generalized entropy principle could be used to evaluate the BGBCCHP system operated under different operating strategies. The BGBCCHP system operated following the electric load achieved the maximum eigenvalue, which showed that its best integrated performance. On the contrary, the BGBCCHP system operated following the thermal load achieved the minimum eigenvalue, which showed that its worst integrated performance. The impact of sensitivity factors on the eigenvalues of the BGBCCHP system was different, which showed that the integrated performance of the BGBCCHP system was closely related to such factors. [ABSTRACT FROM AUTHOR]

A novel type of perforated travelling wave pick-up/kicker structure was developed for CSRe stochastic cooling which was originally proposed by F. Caspers at CERN. The simulated and measured results of shunt impedance of the slotted travelling wave pickup electrode are in reasonable agreement. In December 2015 stochastic cooling of heavy ions was successfully applied for the first time at the CSRe storage ring of IMP in Lanzhou, China. During four days of commissioning, transverse and longitudinal cooling could be observed. Both the time-of-flight and the notch filter methods were used for longitudinal cooling. The measured cooling rates are presented. [ABSTRACT FROM AUTHOR]