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Abstract Outdoor atriums have recently been applied with increasing frequency for natural illumination, but they produce a harsh thermal environment easily in summer. Moreover, overheating of the outdoor atrium necessitates air-conditioning to moderate indoor thermal comfort. Simultaneously, the substantial heat emissions from air-conditioning outdoor units worsen the outdoor thermal environment, creating a vicious cycle. Traditional passive evaporative methods involving water and greenery, while capable of regulating the thermal environment, suffer from low evaporative efficiency and pose significant challenges. To improve thermal environment in outdoor atriums, the spray system was employed due to its high cooling efficiency, especially in open or semi-open spaces. In this study, a comparative experiment was conducted to evaluate the effectiveness of using a spray system for evaporative cooling in open outdoor spaces. Furthermore, employing high-efficiency evaporative cooling through spraying to disrupt the vicious cycle of indoor and outdoor thermal environments. The dual goals include regulating indoor and outdoor thermal conditions while also mitigating the local heat island effect. Temperature and humidity distribution within the atrium and adjacent hallways were monitored, along with the impact on air-conditioning operation consumption in neighboring offices. Results showed that the spray system significantly improved the thermal environment in the outdoor atrium, reducing the average and peak air temperatures by 0.94–2.83 °C and 2.92–5.21 °C, respectively. It also resulted in a drop in the average temperature by 0.56–1.62 °C and the peak temperature by 2.31–3.25 °C in adjacent hallways. This effectively eased the issue of overheating in these areas while raising the comfort level in adjacent office spaces. The predicted mean vote decreased from 1.46 to 0.87, indicating a significant improvement in thermal environment in neighboring offices. Furthermore, the daily energy consumption was reduced by 10.6–12.4% in neighboring offices. This study provided the valuable guidance for improving thermal environments within outdoor atrium.

Abstract Amid the escalating global climatic challenges, hydrological risks significantly influence human settlement patterns, underscoring the imperative for an in-depth comprehension of hydrological change’s ramifications on human migration. However, predominant research has been circumscribed to the national level. The study delves into the nonlinear effects of hydrological risks on migration dynamics in 46,776 global subnational units. Meanwhile, leveraging remote sensing, we procured globally consistent metrics of hydrological intrusion exposure, offering a holistic risk assessment encompassing hazard, exposure, and vulnerability dimensions, thus complementing previous work. Here, we show that exposure is the primary migration driver, surpassing socioeconomic factors. Surrounding disparities further intensified exposure’s impact. Vulnerable groups, especially the economically disadvantaged and elderly, tend to remain in high-risk areas, with the former predominantly migrating within proximate vicinities. The nonlinear analysis delineates an S-shaped trajectory for hydrological exposure, transitioning from resistance to migration and culminating in entrapment, revealing dependence on settlement resilience and adaptability.

Phase-change materials (PCM) can effectively improve the thermal performance of lightweight buildings, but their heat storage and release capacity are highly dependent on the heat exchange between the wall surface and the ambient environments. However, the current research mostly focuses on numerical simulation in a specific climate environment, and the effectiveness of PCM on the thermal regulation of lightweight buildings under a long-period natural environment is insufficient. Therefore, two experimental rooms (with and without PCM) of the same size were built and conducted in this paper to compare the changing rules of wall surface temperature, heat flux, and indoor temperature in different seasons without mechanical equipment. The results show that: (1) The effect of PCM on the thermal performance of lightweight buildings is highly correlated with seasons, and its contribution efficiency varies in different seasons; (2) The attenuation rate of the internal surface temperature in different seasons can be reduced by 18.08%–42.90 %, the delay time can be improved to 2.67–4 h compared with the reference wall; (3) PCM can effectively inhibit the fluctuation and rise of indoor temperature, which can reduce the maximum indoor temperature by 4.9–12.0 °C, increase the minimum temperature by 1.1–2.8 °C, and the thermal comfort hours added by 2–5 h; (4) Lightweight buildings incorporating PCM can saves 18.69 % and 49.63 % for the peak cooling in summer and transition seasons, and 15.9 % for the heating in winter. The research results can provide the theoretical basis and experimental support for the efficient application of PCM in lightweight buildings.

The application efficiency of the Dynamic Rotating Latent-Energy-Storage Envelope (DRLESE) system is highly contingent upon dynamic rotation timings. To gain the optimal rotation timings, six different timings were examined by employing the liquid fraction, thermal storage and release, surface temperature and heat flow. The numerical heat transfer method was employed and verified an experiment. Results indicated that the optimal initial rotation occurs in the forenoon, when the inner surface temperature aligns with the sol-air temperature. Subsequently, achieving optimal secondary rotation is possible in the afternoon when the sol-air temperature equals the liquid temperature of PCM (Phase Change Material). Under these optimized initial and secondary rotation timings, the significant enhancements in thermal performance of the DRLESE system were observed. By optimizing rotation timings, indoor effective heat release can reach up to 3182.9 kJ/Day with an effectiveness percentage exceeding 99.99%, and inner surface heat flow was increased by 5.86%–12.26%.

The conventional latent-energy-storage-envelope relies solely on the phase changes of Phase-Change Materials (PCMs) to regulate heat transfer, thereby lacking the effectiveness in active indoor heating or cooling. To overcome this technical barrier, the Dynamic Rotating Latent-Energy-Storage Envelope (DRLESE) was proposed to achieve active indoor heating by rotating the PCM layer. The DRLESE can absorb solar gain efficiently and release thermal energy directly indoors. In order to assess the application efficiency of DRLESE, two high-insulation walls incorporating a PCM layer were constructed, with the static one serving as a reference. A numerical heat transfer method was employed and verified an experiment. The numerical results demonstrated that compared to the Static Latent-Energy-Storage Envelope (SLESE), the DRLESE system can release stored thermal energy directly indoors by rotating the PCM layer near the interior, resulting in a released heat flow ranging from −22W/m2 to −80W/m2. However, due to differences in the heat release environment, DRLESE exhibits a lower thermal release rate leading to a reduction of up to 33.8 %∼34.8 % in its thermal release and storage capacity. The DRLESE not only limits thermal dissipation from outdoors but also provides indoor heating, while it provides the thermal energy per unit area to minimize the cooling load of the SLESE with 10.39 m2∼14.10 m2. Finally, it is identified on the present deficiencies and limitations for further the comprehensive investigations.

Widespread adoption of air-conditioning significantly enhances indoor thermal comfort in summer, but the heat dissipation from these outdoor units contributes to an increase in ambient air temperature, exacerbating urban heat island effects. Consequently, as outdoor thermal conditions worsen, the energy consumption associated with air-conditioning is likely to escalate. The spray system becomes a suitable choice due to the obvious advantage of heat absorption through the droplet evaporation. To assess the effectiveness of the spray system in reducing heat release, a comparative study was conducted between two identical buildings with the same air-conditioning system, but only one of which incorporated the spray system. Three installed locations are considered with the spray location in inlet (Case 1), outlet (Case 2) and both inlet & outlet (Case 3) of outdoor units. The results demonstrated the average temperatures of air outlet were reduced by 4.0 °C, 6.3 °C, and 7.9 °C for Cases 1–3, respectively, accompanied by a reduction in energy consumption of the air-conditioning system by 18.8%, 13.9%, and 37.3% respectively. The most significant benefits were observed when the spray location was installed in both outdoor unit inlet and outlet (Case 3). The spray system established a virtuous cycle in heat dissipation improvement, evaporation enhancement, and air temperature reduction.

ABSTRACTIn China, 45% of adolescents with obesity develop fatty liver disease, a condition that increases the long-term risk of developing cirrhosis and liver cancer. Although the factors triggering nonalcoholic fatty liver disease (NAFLD) vary in children, the composition of intestinal microflora has been found to play an increasingly important role. However, evidence is limited on the prevalence of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) in Chinese children. Therefore, this study aimed to evaluate the fecal microbiome of Chinese children with NAFLD and further analyze the potential of flora in regulating NAFLD-related symptoms and metabolic functions. Specifically, the study applied a 16S rRNA and metagenomic sequencing to the fecal samples of pediatric patients with NAFLD, NASH, and NAFL, as well as healthy controls, to explore the correlation among NAFLD-related indexes, metabolic pathways, and gut flora. The findings showed that some fecal microbiota had a negative correlation with body mass index, and various NAFLD-related bacteria, including Lachnoclostridium, Escherichia-Shigella, and Faecalibacterium prausnitzii, were detected. Consequently, the study concluded that the variation in gut microbiota might be more important in improving NAFLD/NASH compared with single species, providing a microbiota diagnostic profile of NAFLD/NASH.IMPORTANCEThis study aims to characterize the gut microbiota in Chinese children with nonalcoholic fatty liver disease (NAFLD) through 16S rRNA and metagenomic sequencing. The results highlight the association between fecal microbiota and NAFLD in Chinese children, demonstrating distinct characteristics compared to adults and children from other countries. Based on the sequencing data from our cohort’s fecal samples, we propose a microbiota model with a high area under the curve for distinguishing between NAFLD and healthy individuals. Furthermore, our follow-up study reveals that changes in the relative abundance of microbial biomarkers in this model are consistent with variations in patients’ body mass index. These findings suggest the potential utility of the microbiota model and microbial biomarkers for diagnosing and treating NAFLD in children.

Nowadays, evaporatively cooled office buildings commonly observed in dry hot areas in summer of China. However, few dedicated studies to record the local residents' thermal comfort and adaptability in these buildings. The contribution of adaptive comfort theory on thermal perception still remains unclear for optimizing office building design parameters. Hence, to deeper probe the adaptive thermal comfort of the related indoor environment, a field study of office buildings during summer considering evaporative cooling air conditioned (ECA) and naturally ventilated (NV) mode was conducted in Turpan, China. Based on 931 valid datasets collected from questionnaires, we found that the neutral temperature (Tn) of 28.4 °C in ECA group, 0.6 °C lower than NV group (29.0 °C). A lower air temperature (Ta) and higher humidity (RH)/air-velocity (Va) were expected in two modes, and Va has a stronger influence than RH on mean thermal sensation votes (MTSV). Meanwhile, occupants can adapt to current indoor environment through physiological, psychological and behavioral adjustments, while the clothing regulation had limited effect on MTSV unless the outdoor temperature exceeds 38 °C. Whether in ECA or NV mode, the predicted mean votes (PMV) model overestimated actual thermal sensation when operative temperature (Top) beyond 28 °C. Adaptive models were also proved varied from that in current standards, which indicated that they were not suitable for evaluating the studied buildings in Turpan. Above findings could suggest us a better understanding of the occupants' thermal adaptability, thereby providing the reference of design parameters revision and passive strategies for local newly/renovated buildings.

Solar Air Collectors integrated with Phase-Change Material (SAC-PCM) were widely used for wintery heating with the superiority of overcoming the mismatch shortcoming between supply and demand time from solar heating. However, the traditional SAC-PCM had the low-efficiency heat output due to the low air flow of natural convection. Based on this, a fan was proposed to enhance air flow and thereby, increase the heat output from SAC, so an experiment was built to compare the thermal performance between SAC-PCM and SAC-PCM with a fan (SAC-PCM-F). The experimental result showed that the fan enhanced the outlet wind speed from 0.8 m/s-1.55 m/s to 2.15 m/s-2.3 m/s and by employing the fan, the heat output was easier from SAC-PCM and the average temperatures of outlet air were increased 4.18 °C in all day with the average temperature difference of outlet and inlet air increased by 1.17 °C. Employing the fan could improve indoor average temperature by 1.17 °C, while the daily heat output was increased by 146.02% by employing the fan and the heat collecting efficiency was increased from 24.92% to 61.32%

Pedestrians will experience different heat stress stages from sunlight to semi-open spray space as they shuttle through stations with spray systems. There are few studies on the influence of thermal experience and thermal history of this specific environment on pedestrian thermal comfort. This study explored the dynamic physiological thermal response and thermal perception of humans in the sunlight to semi-open spray space in Qingdao, China. Meteorological and physiological parameters were measured and questionnaires were conducted. The results showed that from outdoor sunlight to semi-open spray space, thermal sensation and thermal comfort were improved, the mean skin temperature of the whole body decreased by 0.5 °C, the neutral standard effective temperature (NSET*) enhanced by 8.8 °C, and the NSET* range (NSET*R) increased by 7.3–10.2 °C. However, after 10 min in the semi-open spray space, the thermal comfort gradually deteriorated. In addition, the main meteorological factors affecting the thermal sensation in sunlight and semi-open spray space were air temperature and mean radiant temperature, and the main physiological factor was the skin temperature of the right upper arm. This study is helpful for the operation design of spray systems and the evaluation of the thermal environment in semi-open spray in cities.

Solar air collectors (SAC) are widely used for the wintery heating, but they have a mismatch shortcoming between supply and demand periods of heat quantity. Integrating phase change material (PCM) into solar air collectors was usually employed to overcome this mismatch, but it was proved that the heat loss through the glass covers reduced utilization efficiency largely in the actual application. According to this, the study employed PCM and nocturnal thermal insulation (NTI) to overcome the mismatch between supply and demand time and improve the nocturnal thermal insulation performance, respectively. Three air collectors (traditional SAC, collector integrated with phase change material (SAC-PCM), collector integrated with both phase change material and nocturnal thermal insulation (SAC-PCM-NTI)) were built to analyze the influence. Experimental results showed PCM could change the heat output time by the latent storage, but the low thermal insulation of the glass plate caused the much heat loss and reduced the thermal efficiency obviously. Employing NTI was highly efficient for collectors which PCM by reducing the heat loss, while it could increase the average temperature of indoor air by 2.49 °C. Employing PCM could reduce the heat collecting efficiency by 13%–21% due to the much heat loss during the heat storage and release processes, while using NTI could increase heat collecting efficiency from 24.46% to 32.63%.

Employing split air conditioners (SAC) for indoor heating is common, but the poor air quality usually occurs due to lack of fresh air and low relative humidity in winter. The indoor living wall (ILW) has become a reasonable option to refine the indoor heating environment through their purification and photosynthesis. To improve the heating environment, ILW were integrated with the SAC. The system integrating the ILW with the SAC (ILW-SAC) was installed in a common room with referring to the other identical room only having the SAC. The indoor thermal environment and CO2 concentration were tested, while the 72 participants were invited to demonstrate their feelings by using skin temperature measurements. The results showed that ILW-SAC significantly improved the indoor environment by increasing relative humidity by 10.8%, controlling air speed between 0.2 m/s and 0.3 m/s, and reducing CO2 concentration by 49 ppm. ILW-SAC lowered the mean skin temperature by 0.4 °C and let the mean skin temperature closer to the neutral value. ILW-SAC was found to improve the overall freshness sensation and thermal comfort level by about 1.32 and 1.10 respectively. By employing ILW-SAC, the indoor thermal environment and air quality are refined significantly in winter.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become the most common coronavirus that causes large-scale infections worldwide. Currently, several studies have shown that the ABO blood group is associated with coronavirus disease 2019 (COVID-19) infection and some studies have also suggested that the infection of COVID-19 may be closely related to the interaction between angiotensin-converting enzyme 2 (ACE2) and blood group antigens. However, the relationship between blood type to clinical outcome in critically ill patients and the mechanism of action is still unclear. The current study aimed to examine the correlation between blood type distribution and SARS-CoV-2 infection, progression, and prognosis in patients with COVID-19 and the potential mediating role of ACE2. With 234 patients from 5 medical centers and two established cohorts, 137 for the mild cohort and 97 for the critically ill cohort, we found that the blood type A population was more sensitive to SARS-CoV-2, while the blood type distribution was not relevant to acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and mortality in COVID-19 patients. Further study showed that the serum ACE2 protein level of healthy people with type A was significantly higher than that of other blood groups, and type O was the lowest. The experimental results of spike protein binding to red blood cells also showed that the binding rate of people with type A was the highest, and that of people with type O was the lowest. Our finding indicated that blood type A may be the biological marker for susceptibility to SARS-CoV-2 infection and may be associated with potential mediating of ACE2, but irrelevant to the clinical outcomes including ARDS, AKI, and death. These findings can provide new ideas for clinical diagnosis, treatment, and prevention of COVID-19.

Productive facades, consisting of photovoltaic shading and vertical farming systems, have been proposed as a means to improve the thermal and visual status of residential buildings while also maintaining energy performance and providing vegetables. However, how to quickly and accurately predict electricity and vegetable output during the numerous influencing architectural and environmental factors is one of the key issues in the early stages of design, and few studies have investigated the impact of such structures on both indoor environmental qualities and production performance. In this paper, we present a novel prediction method that uses experimental data to train and test an artificial neural network (ANN). The results indicated that using the Bipolar Sigmoid activation function to process the experimental data input to the artificial neuron network gives more accurate predicted results both in the yield of photovoltaic shading and vertical farming systems. In addition, this prediction method was applied to a typical high-rise residential building in Singapore to assess the self-sufficiency potential of high-rise residential buildings integrated with productive facades. The results indicated that the upper part of the building can meet 20.0–23.1% of the annual household electricity demand of a family of four in a four-room residential unit in Singapore and almost the entire year’s vegetable demand, while the middle part can meet 18.4–21.2% and 89.1%, respectively. The results demonstrated the importance of a productive facade in reducing energy demand, enhancing food security, and improving indoor visual and thermal comfort.

Thermochromic materials can adjust their formal reflectivity in response to changes in ambient temperature, so they offer a means of achieving seasonal thermal control and have been a reasonable choice to enhance the solar radiation heat in winter and lower the solar radiation heat in summer. To optimize thermochromic coatings to meet the application requirement on architectural surface color, the effect of the material color was studied on optical properties of thermochromic coatings under two transition temperatures of 25 °C and 33 °C. A measurement system was designed to analyze the reflectivity spectra and solar reflectivity of thermochromic coatings in both colored and colorless phases. Experimental results show that all samples exhibited a significant increase in reflectivity from the colored phase to the colorless phase especially in the 1300 nm–1600 nm and 1900 nm–2100 nm wavelengths. The global reflectivity of the thermochromic coatings could be increased by 3.17%–10.68% under 25 °C and 7.22%–18.23% under 33 °C. From the view of evaluating the optical properties, the purple-blue and dark-green colors are respectively the best choices for thermochromic coatings. The experimental data proposed the efficient reference for application of thermochromic materials in buildings.

Emerging epidemiological evidence has linked per- and polyfluoroalkyl substances (PFAS) exposure could be linked to the disturbance of gestational glucolipid metabolism, but the toxicological mechanism is unclear, especially when the exposure is at a low level. This study examined the glucolipid metabolic changes in pregnant rats treated with relatively low dose perfluorooctanesulfonic acid (PFOS) through oral gavage during pregnancy [gestational day (GD): 1–18]. We explored the molecular mechanisms underlying the metabolic perturbation. Oral glucose tolerance test (OGTT) and biochemical tests were performed to assess the glucose homeostasis and serum lipid profiles in pregnant Sprague-Dawley (SD) rats randomly assigned to starch, 0.03 and 0.3 mg/kg·bw·d groups. Transcriptome sequencing combined with non-targeted metabolomic assays were further performed to identify differentially altered genes and metabolites in the liver of maternal rats, and to determine their correlation with the maternal metabolic phenotypes. Results of transcriptome showed that differentially expressed genes at 0.03 and 0.3 mg/kg·bw·d PFOS exposure were related to several metabolic pathways, such as peroxisome proliferator-activated receptors (PPARs) signaling, ovarian steroid synthesis, arachidonic acid metabolism, insulin resistance, cholesterol metabolism, unsaturated fatty acid synthesis, bile acid secretion. The untargeted metabolomics identified 164 and 158 differential metabolites in 0.03 and 0.3 mg/kg·bw·d exposure groups, respectively under negative ion mode of Electrospray Ionization (ESI-), which could be enriched in metabolic pathways such as α-linolenic acid metabolism, glycolysis/gluconeogenesis, glycerolipid metabolism, glucagon signaling pathway, glycine, serine and threonine metabolism. Co-enrichment analysis indicated that PFOS exposure may disturb the metabolism pathways of glycerolipid, glycolysis/gluconeogenesis, linoleic acid, steroid biosynthesis, glycine, serine and threonine. The key involved genes included down-regulated Ppp1r3c and Abcd2, and up-regulated Ogdhland Ppp1r3g, and the key metabolites such as increased glycerol 3-phosphate and lactosylceramide were further identified. Both of them were significantly associated with maternal fasting blood glucose (FBG) level. Our findings may provide mechanistic clues for clarifying metabolic toxicity of PFOS in human, especially for susceptible population such as pregnant women.

Abstract Sensing is an essential part in autonomous driving and intelligent transportation systems. It enables the vehicle to better understand itself and its surrounding environment. Vehicular networks support information sharing among different vehicles and hence enable the multi‐vehicle multi‐sensor cooperative sensing, which can greatly improve the sensing performance. However, there are a couple of issues to be addressed. First, the multi‐sensor data fusion needs to deal with heterogeneous data formats. Second, the cooperative sensing process needs to deal with low data quality and perception blind spots for some vehicles. In order to solve the above problems, in this paper the occupancy grid map is adopted to facilitate the fusion of multi‐vehicle and multi‐sensor data. The dynamic target detection frame and pixel information of the camera data are mapped to the static environment of the LiDAR point cloud, and the space‐based occupancy probability distribution kernel density estimation characterization fusion data is designed , and the occupancy grid map based on the probability level and the spatial level is generated. Real‐world experiments show that the proposed fusion framework is better compatible with the data information of different sensors and expands the sensing range by involving the collaborations among multiple vehicles in vehicular networks.

Wearing Personal Protective Equipment (PPE) is essential to protect healthcare workers during the COVID-19, but the traditional cooling methods do not meet the requirements of epidemic prevention during the COVID-19. Therefore, the cooling clothing integrated with phase change material (PCM-CC) was proposed for healthcare workers performing nucleic acid sample collection outdoors. Human experiments and subjective questionnaires were used to test the effect of wearing PCM-CC on the thermal sensations of healthcare workers and to analyze the effectiveness of PCM-CC in relieving thermal stress and thereby, improving the thermal comfort of healthcare workers. Results showed that wearing PCM-CC was effective in alleviating various heat symptoms associated with wearing PPE in a hot-temperature environment. Wearing PCM-CC reduced head and facial discomfort by 25% and 41% under the 26 °C thermal environment, while it improved the mean thermal sensation vote (TSV) values by 0.71 and 1.85 under the 26 °C and 32 °C thermal environments, respectively, and made the mean TSV value close to the neutral value. Meanwhile, wearing PCM-CC reduced mean skin temperatures by 0.65 °C, and the pronounced cooling effect was found in the chest. Wearing PCM-CC could be an effective thermoregulation measure to refine the thermal comfort of healthcare workers during the COVID-19 pandemic.

Two-phase closed thermosyphons (TPCTs) are effective devices for transferring heat and could be used to reduce the internal heat of coal piles, inhibiting coal spontaneous combustion. Nanofluids have recently been investigated as working media for improving the thermal efficiency of TPCTs by exploiting the high thermal conductivity of nanoparticles. In this study, the heat transfer performance of a TPCT containing CuO–H2O nanofluids of various nanoparticle concentrations was investigated experimentally and through simulations for a coal pile at different operating temperatures (373.15, 413.15, 473.15, and 573.15 K). At 373.15 K, the optimal CuO–H2O concentration was 10 mass%, which was associated with a 34.5% improvement in heat transfer. At 413.15, 473.15, and 573.15 K, the optimal CuO–H2O concentration was 15 mass%, with the corresponding heat transfer improvements being 8.1%, 41.9%, and 40.8%, respectively. At higher operating temperatures, the thermal resistance of the TPCT decreased and the heat transfer performance increased. In particular, at 473.15 and 573.15 K, increasing the nanoparticle concentration improved heat exchange in the working medium, increasing the heat transfer efficiency. These results could be used to further optimize TPCTs and by practitioners to reduce the risk of coal fires.

The thermal storage system is widely used to reduce the mismatch between thermal energy supply and demand in time and space, and its thermal performance is a critical factor in the system's thermal efficiency. The thermal performance of the Sensible Thermal Energy Storage Unit (STESU), the Latent Thermal Energy Storage Unit (LTESU), and the LTESU integrated with Copper Foam Fin (CFF) were compared through comparative experiments. The experimental results showed that the thermal changing rate of STESU was higher than that of other units, and there was no apparent thermal stratification. However, LTESU had the lowest thermal changing rate with apparent thermal stratification. During the thermal charging process, the solid-liquid interface on the LTESU cross-section formed an inverted-triangle shape. The lower part of the PCM could not change its phase as a dead zone and failed to participate in the thermal charging and discharging. Even so, the thermal efficiency of LTESU was 18.7% higher than that of STESU. Integrating with CFF could increase the thermal charging capacity, the thermal discharging capacity and the thermal efficiency by 51.1%, 55.9% and 10.8%, respectively.

Phase-change material (PCM) has been widely employed to improve the wall thermal performance, but its contribution efficiency was impacted by wall forms and thereby, it was very important to analyze the wall adaptability of the PCM layer. According to this condition, three typical walls had been built with the different thermal inertias. A numerical model was built with the heat transfer process of melting-solidifying and a model experiment was done to verify this numerical model. The numerical results showed the attenuation coefficients were reduced by 8.76%, 7.54% and 2.02% for the light-weight, middle-weight, and heavy-weight walls, while the time lag was increased by 4.83 h. Due to adding the PCM layer, inner surface heat flow fluctuated more gently. The removed peak heat quantities were 23.48%, 19.29% and 6.60% of the daily heat flow values with reducing the peak heat flows by 32.16w/m2, 25.54 w/m2 and 6.28 w/m2 for the light-weight, middle-weight, and heavy-weight walls respectively. The PCM layer had the higher contribution efficiency in the light-weight and middle-weight walls, but its contribution efficiency was too low to be highly valued in the heavy-weight wall.

Phase change materials (PCM) can improve the thermal performance of lightweight building walls (LBW), but the effect is not only dependent on the PCM parameters but also high on the heat exchange between the surface and the ambient environment. For actual buildings, there are differences in the outdoor thermal environment of the walls in different directions, especially the solar radiation intensity. Therefore, a small-scale lightweight building was made in this study and its thermal environment in different directions were tested. Then, the influence rules and suitability of PCM parameters on the thermal performance of LBW in different directions were analyzed by developing a typical two-dimensional heat transfer model. The results show that the application effects and suitable parameters of PCM in walls in different directions are different. PCM location (phase-transition temperature) is adapted to the middle (20–30 °C) for the east and south-facing wall, while the inside (18–28 °C) and outside (24–34 °C) is optimal for the west and north-facing wall. The thermal performance improvement with the most noticeable in the east and west-facing walls at suitable PCM parameters and their peak and average heat flux can be reduced by 62.8–66.4% and 28.2–29.5%, and delay time increased by 5–5.34h compared to reference wall.

Retro-reflective (RR) materials have received much attention due to their retro-reflective optical properties, which has essential differences with the diffuse reflection of traditional highly-reflective materials. As a guide to determine the performance improvement and the building applications of RR materials, the spectral characteristics are measured and related to the typical glass-bead and prism RR materials. The integrating sphere is used to measure the global reflectivity of the two RR materials, while a new instrument is developed to study the angular distribution and the retro-reflectivity of two RR materials at different incident angles. The results show that the global reflectivity is found to be 68.08% and 51.44% for the glass-bead and Prism RR materials, respectively, but the retro-reflectivity of the prism RR material is 12.56% higher than that for the glass-bead RR materials. The RR materials display the greatest different for the retro-reflectivity under the different radiation wavelengths. The variation trend of the retro-reflectivity is distinct for different wavelength ranges: the higher the wavelength, the lower the retro-reflectivity. Increasing the incident angle could reduce the retro-reflective property of the RR materials, and the incident angle had a high impact on radiation wavelengths less than 1200 nm. With the incident angle increased from 0° to 80°, the retro-reflectivity is reduced by 40.58–48.60% for the 800 nm wavelength, 35.40–45.13% for the 900 nm, 23.43–26.01% for 1000–1200 nm, and 8.64–13.71% for 1300–1600 nm.

To achieve carbon neutrality in 2060 (China), building energy-saving has been highly concerned. University buildings have great energy-saving potential as part of energy consumption where 70% of energy loss is caused by heat transfer from the envelope. However, most of the research on energy-saving factors for envelopes is limited to a certain climate or a specific building type, and the optimal configuration of envelopes under different climatic regions has not been well solved. Therefore, the influence degree and appropriate parameters of each factor of the teaching-office building envelopes on energy consumption under different climates were analyzed in this paper by orthogonal design and numerical simulation. Results show that: (1) Solar heat gain coefficient (SHGC) and indoor air change rates (ACH) [the heat transfer coefficient of the exterior wall (Kwall) and ACH] are the main factors affecting the cooling [heating] load, the insulation form of the exterior wall (Wins) and Kwall [Wins and solar radiation absorption coefficient of exterior surface materials (ρs)] have less influence; (2) The important ranking and optimal level of the influence of each factor on the cooling (or heating) loads are related to local load demands; (3) For the annual load, Kwall and the heat transfer coefficient of the exterior window (Kwin) is the focus of energy-saving in severe cold and cold zones, but their impact is not significant in Guangzhou and Kunming, and the high significance of SHGC is only shown in Hohhot, Lhasa, Guangzhou, and Haikou; (4) The annual load energy savings reach 39.64%–57.57% in different climates by optimizing all factors. The research results can provide directions and data references for the energy-saving design and renovation of educational building envelopes in different climates (China).

Phase-change materials (PCM) can effectively improve the thermal performance of lightweight building walls (LBW), but their contribution efficiency is related to PCM parameters and the thermal resistance of the original walls (Rwt). Therefore, a heat transfer model of LBW integrated with PCM was built and validated in this paper, and the influence rules and contribution efficiency of PCM parameters on the thermal performance of LBW with different Rwt were analyzed and evaluated by numerical simulation. The results show that: (1) The suitable phase-transition temperature is more influenced by the PCM location and less by Rwt, and the middle of wall and 22–32 °C is the best choice for PCM; (2) The PCM parameter values are not proportional to the improvement of thermal performance and its influences are more noticeable as the Rwt decreased, and their optimal values and its contribution efficiency are diminished with Rwt is boosted; (3) The PCM contribution efficiency is reduced by 56.61%(attenuation rate), −34.3%(delay time), 58.31%(peak heat flux) and 61.78%(average heat flux) as the Rwt [(m2·K)/W] is increased from 2.0 to 5.0 under the suitable PCM parameters. The findings provide data support and theoretical reference for the application of PCM in different types of lightweight buildings.

In recent years, lightweight buildings have been widely developed due to their sustainability advantages. However, lightweight buildings usually have sizeable indoor temperature fluctuations due to lower thermal mass. Phase change materials (PCM) have the characteristics of small temperature change and high energy storage density. Integrating PCM into lightweight building walls (LBW) can effectively enhance its thermal inertia and improve indoor thermal comfort. There are many discussions on building energy saving using PCM in the existing studies, but the research on the influence of PCM parameters on the thermal performance of LBW is insufficient. Therefore, a heat transfer model of LBW integrated with PCM was built and validated in this paper. The influence rules of different PCM parameters (transition temperature, location, thickness, latent heat, thermal conductivity, density, specific heat) on the thermal performance of LBW was analyzed and evaluated comprehensively by numerical simulation. The results show that: (1) PCM can significantly improve the thermal performance of LBW; (2) Each parameter of PCM has a relative optimal value; (3) PCM installed in the middle of the wall is better than the outside or inside at a suitable phase-transition temperature; (4) Under suitable PCM parameters compared with the reference wall (no PCM), the delay time (φ) is added to 6.86 h, the attenuation rate (f) decreases by 90.45%, the peak heat flux (qpeak) and average heat flux (qave) is reduced by 66.52% and 33.39%. The research results can provide reference and data support for the use of PCM in lightweight buildings.

Integrating Phase-Change Material (PCM) in building walls has been an effective technological method to improve wall thermal performance, but its contribution efficiency has been impacted by the thermal performance of original walls. To explore the influence laws of wall thermal performance on the contribution efficiency of the PCM layer and then find the suitable application of the PCM layer, the numerical simulation verified by an experiment was done for wall physical models with different thermal performance. Experimental results revealed that the temperature amplitudes of the inner surface and indoor air were reduced by 25.13 °C and 20.86 °C respectively due to adding the PCM layer in the light-weight building models. Numerical results showed integrating the PCM layer increased the time lag, but this contribution efficiency had the poor correlation with the heat transfer coefficient and the thermal inertia. Moreover, the contribution efficiency from the PCM layer would be increased on the decrement factor and the peak heat flow with an increase of the heat transfer coefficient or reducing the thermal inertia. The core contribution from the PCM layer is not thermal insulation improvement, but thermal adjustment enhancement and thereby, the contribution of integrating the PCM layer was ignored on the average heat flow.

Both vegetation coverage rates and arrangement patterns have important influences on erosion. Very little previous research focuses on the impacts of spatial vegetation distribution patterns on erosion. The slope-gully system was taken as the research object, which is composed of a 5.0 m long hillslope with a slope gradient of 20° and a 3.0 m long gully slope with a gradient of 50°. A series of scouring experiments with two inflow discharges (3.2 L min−1, 5.2 L min−1) was carried out. The effects of the flow discharges, spatial grass arrangement patterns (US, MS, and DS represent the presence of grass covering on up-hillslope, middle-hillslope, and down-hillslope, respectively) and grass coverage rates (0%, 30%, 50%, 70%, and 90%) on runoff and sediment were studied in this paper. The results indicated that either runoff or sediment yielding was significantly decreased with the grass coverage rates increasing and with the variation of grass arrangement patterns on a hillslope. While grass coverage had more effectiveness in controlling erosion compared with runoff reduction, and DS can control erosion more effectively than US and MS erosion controlling. For the gully slope, erosion significantly increased with the grass coverage rates increasing no matter how the grass arrangement patterns on the hillslope. Therefore, both different grass coverage and different grass arrangement patterns have an influence on erosion processes; any research that only takes care of the single factor mentioned above is not enough to reveal the effects of grass on erosion. In the process of erosion control in the Loess Plateau, taking effective measures both on the hillslope and gully slope will be effective methods of reducing soil erosion.

Plants have the potential to reduce CO2 concentration, but their photosynthesis is directly influenced by the indoor lighting environment. As a result, the efficiency of indoor plants is limited by indoor lighting environment. In order to explore the effect of lighting environments on the reduction of indoor CO2 concentration by indoor plants, three representative lighting environments were constructed, including a natural lighting environment, a poor lighting environment and an all-day lighting environment, while five common plants were selected to be planted in five transparent sealed chambers. Experimental results show that the lighting environment affected the CO2 concentration largely in transparent sealed chambers. Compared to the transparent sealed chamber without plants, the highest and average CO2 concentrations were increased by from 47.9% to 160.9% and from 21.6% to 132.4% in the poor lighting environment, respectively, while they decreased by from 60.4% to 84.6% and from 71.4% to 89.7% in the all-day lighting environment. This indicated that plants did not purify the indoor air consistently. Among the selected plants, the most suitable houseplant was Scindapsus aureus, followed by Chlorophytum comosum and Bambusa multiplex.

Since the self-insulation wall has the same service life as the building, the resources are saved, and the environmental pollution is reduced, so it has been widely used. In order to obtain the optimal filling position and filling rate of the composite self-insulation hollow block, the thermal insulation performance of the composite self-insulation hollow block was optimized. In this experiment, 6 groups of self-insulating block models with different filling positions and filling rates were constructed. A cold and hot test box was used to simulate the working state of 6 groups of composite self-insulation blocks in the continuous operation of air conditioning in cold areas of China in winter. Through comparative analysis: Filling the hollow block with EPS insulation material is conducive to improving the insulation performance of hollow brick, and the higher the EPS filling rate is, the better the insulation performance of the block is. At the same EPS filling rate, the closer EPS is to the inside of the heat box, the better the insulation effect of the wall will be. At the same EPS filling rate, the method of filling EPS on both sides of the cavity has the best insulation effect, which is conducive to saving insulation materials.

In this study, the influence of the inclination angle was analyzed on the thermal behavior of PCM in the cavity filled with copper foam fins. Twelve inclination angles from 0° to 360° were studied for the thermal storage unit, while the two-temperature equation thermal transfer model was built. The liquid fraction, the temperature response rate, and the average heat flow were employed as evaluation parameters. Numerical results displayed the inclination angle had the great influence on the PCM thermal performance and by optimizing the inclination angle, the whole phase-change time was shortened by 43.16% with the inclination angle from 0° to 180°. In melting and freezing processes, the inclination angle had the opposite rules and affected the thermal performance difference obviously. With the inclination angle from 0° to 180°, the difference values were reduced from 17904s, 712 w/m2 and 0.00867 °C/s to 1709s, 31 w/m2 and 0.00051 °C/s for full phase-change time, the average heat flow and temperature response rate, respectively. And the optimum inclination angle was 180° in the view of a melting and freezing period and the reasonable inclination angle could be selected according to thermal storage and release rules in the engineering application.

There is not yet a standard drug regimen for the treatment of coronavirus disease 2019 (COVID-19) patients. Here, we summarize our experience and successful treatment plan with a critical COVID-19 patient who required mechanical ventilation (MV). A 56-year-old man presented with a fever, cough, and dyspnea. He had not been to a medium/high risk epidemic area in the past year and had no family history of a disease cluster. COVID-19 was suspected based on clinical symptoms and radiologically detected ground-glass lung changes in the context of a normal white blood cell count (WBCC) and lymphocyte fraction (L%). A diagnosis of COVID-19 was confirmed by nucleic acid testing. Initially, he was started on noninvasive ventilation (NIV). Because his respiratory distress worsened over the following 2 h, he was transitioned to mechanical ventilation (MV), placed in prone positioning 12 h/day, and given a multi-pronged pharmacotherapy regimen that included an antiviral cocktail (lopinavir/ritonavir plus α-interferon), an immunity enhancer (thymosin α1), an anti-coagulant to prevent thrombosis (heparin). He was given an antibiotic to treat an opportunistic nosocomial infection. The patient has recovered well. The regimen applied in this case of timely evaluation, early prone positioning with MV, and a multi-pronged pharmacotherapy may be an effective strategy for patients with critical COVID-19, particularly with respect to preventing life-threatening worsening of the illness.

Abstract Background Obesity is associated with many chronic diseases including cortisol rhythm disorder and low testosterone. Furthermore, studies on obese children are quite limited and no concordance results have been obtained, especially for boys in puberty. Moreover, the sample sizes of previous studies were small, and were not representative. Methods We conducted a cross-sectional survey including 1148 boys aged 6–14 years, they were divided into overweight/obesity (OW/OB) group and normal weight (NW) group. Puberty status was assessed according to Tanner scale and testicular volume. Serum levels of pregnenolone, 17-OH progesterone, corticosterone, dehydroepiandrosterone (DHEA), and androstenedione were detected by LC-MS. Serum free testosterone and sex hormone-binding globulin (SHBG) levels were measured by chemiluminescence immunoassay. Results The 17-OH progesterone, DHEA, androstenedione and free testosterone levels of OW/OB boys at prepubertal stage or at the age 6 =

Phase-Change Material (PCM) attracted much attention due to its high thermal storage density under the small temperature variation, its poor thermal conductivity limited the thermal charging/discharging efficiency significantly. To overcome this deficit, fins were produced by copper foam to improve the thermal performance of PCM and seven Copper Foam Fin (CFF) shapes were considered with the same filling ratio of 50%. The numerical simulation was employed with the two-temperature non-equilibrium model. Results showed the solidifying process with the liquid fraction variation from 100% to 30% had the similar rules with the melting process with the liquid fraction variation from 0% to 70%, but the solidifying time with the liquid fraction variation from 30% to 0% was much higher than the melting time with the liquid fraction variation from 70% to 100%. The preferable CFF shape was gained with the longer left-side length, close to the hot and cold source. And there was the natural-convection heat transfer in solidifying and melting processes, but the natural convection intensity was too small to be considered in the solidifying process.

Latent thermal energy storage was widely used in many thermal engineering, but the low thermal conductivity of Phase-Change Material (PCM) limited the thermal storage efficiency seriously. Filling metal foam has been an effective way to enhance the heat transfer due to its capability to improve the overall heat conduction effectively. To optimize the thermal performance of the paraffin-metal foam composite PCM, this study analyzed the influence laws of porosity and pore density of copper foam. A two-dimensional numerical model considering two-temperature non-equilibrium equation was built and validated by published results, while the four parameters including the liquid fraction, the temperature response rate, the heat flux, and heat storage capacity were evaluated. The results showed reducing the porosity could improve the thermal behavior of composite PCM especially between 92% and 98%, but it would reduce the heat storage capacity of about 22.3 kJ per the 2% increased porosity. The recommended porosity was 92%. Moreover, increasing pore density could also enhance the thermal behavior of the composite PCM, especially between 5PPI and 15PPI, and it had no influence on the heat storage capacity.

With the acceleration of urbanization throughout the world, climate problems related to climate change including urban heat islands and global warming have become challenges to urban human settlements. Numerous studies have shown that greenways are beneficial to urban climate improvement and can provide leisure places for people. Taking the coastal greenway in Qingdao as the research object, mobile measurements of the microclimate of the greenway were conducted in order to put forward an evaluation method for the research of outdoor thermal comfort. The results showed that different vegetation coverage affected the PET (physiologically equivalent temperature), UTCI (Universal Thermal Climate Index) as well as thermal comfort voting. We found no significant correlation between activities, age, gender, and thermal comfort voting. Air temperature sensation and solar radiation sensation were the primary factors affecting the thermal comfort voting of all sections. Otherwise, within some sections, wind sensation and humidity sensation were correlated with thermal sensation voting and thermal comfort voting, respectively. Both PET and UTCI were found to have a negative correlation with the vegetation coverage on both sides of the greenway. However, the vegetation coverage had positive correlation (R = 0.072) for thermal sensation and significant positive correlation (R = 0.077*) for thermal comfort. The paved area cover was found to have a positive correlation with PET and UTCI, while having a negative correlation with thermal sensation (R = −0.049) and thermal comfort (R = −0.041). This study can provide scientific recommendations for the planning and design of greenway landscapes to improve thermal comfort.

Cancer is a major public health problem and one of the leading causes of death. However, traditional cancer therapy may damage normal cells and cause side effects. Many targeted drug delivery platforms have been developed to overcome the limitations of the free form of therapeutics and biological barriers. The commonly used cancer cell surface targets are CD44, matrix metalloproteinase-2, folate receptors, etc. Once the drug enters the cell, active delivery of the drug molecule to its final destination is still preferred. The subcellular targeting strategies include using glucocorticoid receptors for nuclear targeting, negative mitochondrial membrane potential and N-acetylgalactosaminyltransferase for Golgi apparatus targeting, etc. Therefore, the most effective way to deliver therapeutic agents is through a sequential drug delivery system that simultaneously achieves cellular- and subcellular-level targeting. The dual-targeting delivery holds great promise for improving therapeutic effects and overcoming drug resistance. This review classifies sequential drug delivery systems based on final targeted organelles. We summarize different targeting strategies and mechanisms and gave examples of each case.

When the air-conditioning runs intermittently, there may be the large temperature differences of the indoor air in two adjacent rooms due to the air-conditioning different running behaviors. Under this condition, a lot of the cold quantity was lost through interior walls and then the large cooling load was formed by interior walls. Aimed to this, six typically-employed interior walls were built to compare their thermal performance characteristics under air-conditioning intermittent running. The heat transfer model was built by the finite volume method and verified by the experimental data. The numerical results showed that the air-conditioning running behavior in the adjacent room had an observable influence on temperature response rates and heat flow values in inner surfaces. Compared with the solid brick walls, the daily cooling load formed by interior walls can be reduced by 26.1% for the foamed concrete wall and 12.7% for the hollow brick wall, respectively. When the temperature environment in the adjacent room was beneficial to improving the thermal response rate of the interior wall, the thin wall was the reasonable choice and whereas, the thick wall was the reasonable one. Keywords: Thermal response, Heat flow, Wall thickness, Air-conditioning intermittent running

Wall insulation performance is an important factor affecting building energy consumption and indoor comfortable level. This study proposes that the insulation materials are filled into the cavities of the sintered hollow brick to replace the single insulation layer. The physical models of typical walls were built by the hollow bricks filled with expanding polystyrene board (EPS) in cavities and wall thermal performance is numerically analyzed by the Finite Volume Method under air-conditioning intermittent operation, which conforms to the actual operation rules of air-conditioning. Results show that filling EPS in cavities is beneficial to improve the thermal performance of the bricks, and the larger the EPS filling ratio, the higher the thermal performance improvement. The EPS filling ratio increase has the higher sensitivity on inner surface heat flow under the low EPS filling ratio, and filling EPS in the external cavities is optimum with the decrement rate 5.92% higher than filling EPS in internal cavities for the EPS filling ratio of 20%, while filling EPS in internal and external cavities simultaneously is optimum with decrement rate 2.45%–6.87% higher than that with filling EPS in the internal cavities for the EPS filling ratio of 40%–80%. Keywords: Insulation filling ratio, Insulation filling location, Thermal performance, Sintered hollow bricks

Wall insulation performance is an important factor affecting building energy consumption and indoor comfortable level. The common method to improve the wall insulation performance is to integrate the insulation layer into the built foundation wall, but it increases the construction cost and also delays the construction time due to the twice construction of both the foundation wall and the insulation layer. This study proposes the insulation materials are filled into the cavities of the sintered hollow brick to replace the single insulation layer. To obtain the best filling effect of insulation materials, the typical walls constructed by the hollow brick filled with EPS in cavities are built and wall thermal performance is numerically analyzed. Results show inner surface heat flow is lowest with EPS materials filled into the external cavities of bricks, while inner surface temperature has the longest time lag and the lowest decrement factor with EPS filled into the internal and external cavities simultaneously. And with the increase of the EPS insulation filling ratio, the time lag is increased and the decrement factor is decreased for the inner surface temperature, while the inner surface heat flow is reduced obviously.

Malware detection and homology analysis has been the hotspot of malware analysis.API call graph of malware can represent the behavior of it.Because of the subgraph isomorphism algorithm has high complexity,the analysis of malware based on the graph structure with low efficiency.Therefore,this studies a homology analysis method of API graph of malware that use convolutional neural network.By selecting the key nodes,and construct neighborhood receptive field,the convolution neural network can handle graph structure data.Experimental results on 8 real-world malware family,shows that the accuracy rate of homology malware analysis achieves 93%,and the accuracy rate of the detection of malicious code to 96%.

Although the air-conditioning intermittent operation is widely used in buildings, more attention is focused on the air-conditioning continuous operation in the whole building to simplify energy conservation design, and thereby, the operation method inconsistence of air-conditioning must lead to the large difference between actual value and design value of energy consumption. According to this situation, in order to explore the wall energy conservation difference under the continuous and intermittent operation of air-conditioning, a experiment is built to analyze the effect of the thermal insulation layer location on wall dynamic thermal response rate. Experimental result shows that under the air-conditioning intermittent operation, wall cold storage is the main source of air-conditioning load formed by walls and the wall internal layer has the significant effect on the wall dynamic thermal response performance. And the closer to wall inner surface for the thermal insulation layer, the lower the inner surface temperature and the higher the wall thermal response rate. Meanwhile, the internal thermal insulation wall has the smallest heat flow value, which is less 35–86% than external thermal insulation wall and the sandwich thermal insulation wall, although they have the same heat transfer coefficients.

Due to the low thermal inertia and poor thermal insulation of ultrathin envelope in tents, its indoor temperature environment is extremely bad and its occupants are tormented. Especially under the high solar radiation, both indoor air temperature and inner surface radiation temperature increase rapidly. And thereby, decreasing radiation heat gain in summer is necessary to refine indoor temperature environment in tents. Retro-reflective materials make it a reasonable choice due to their high reflectivity for solar radiation. To reveal the temperature environment improvement of tents by integrating with retro-reflective materials, a comparative experiment is carried out under the summer climatic conditions of Chengdu city, China. Experimental results show that due to integrating with retro-reflective materials, indoor air peak temperature in the tent can be reduced by more than 7.7 °C, while inner surface radiant temperature can be lowered up to 4.8 °C in the day time. It shows retro-reflective materials could refine indoor temperature environment in tents. Through a comparison of the walls in different orientations, on which retro-reflective materials are covered, the top, east and north walls are found to be better choices, while the north wall is the worst one for retro-reflective materials.

Under air-conditioning intermittent operation, indoor air temperature varied sharply with air-conditioning operation behaviour and the much cool capacity was stored to form the cool load by wall materials close to the inner surface, especially for the inner decoration coating. To analyze the effect of the decoration coating on inner surface temperatures and heat flows, four typical walls with the different thermal insulation configurations were built with the different thermal properties of inner decoration coating, while the heat transfer model was established and verified by an experiment. Numerical simulation showed that the inner decoration coating had a significant influence on temperatures and heat flows in inner surface. The reduction of the density, the heat capacity or the heat conductivity coefficient of the decoration coating could obtain the improvement of the temperature response rate and the reduction of heat flow values. And in three studied thermal properties of inner decoration coating, the heat conductivity coefficient had the highest energy-saving efficiency. Keywords: Inner decoration coating, Thermal response, Air-conditioning intermittent operation, Inner surface heat flow

The response rules of the surface temperature with indoor air temperature have been particularly important under the air-conditioning and heating intermittent operation due to their affecting the thermal comfortable level and building energy consumption. In this study, a homogeneity wall was built and the effect of many parameters including the density, the specific heat capacity, the heat conductivity coefficient, the convective heat transfer coefficient, initial temperature and setting temperature of indoor air was analyzed on the response rules of surface temperatures by the analytical solution of the one-dimensional and unsteady heat conduction equation. And a multi-factor coupling regression formula was obtained for the time constant, which was used to evaluate the response rate of inner surface temperature. Keywords: Response rule, Time constant, Theoretical analysis, The multiple linear regression method

The intermittent heating operation is used widely, but the heating behavior status is always ignored to simplify the energy conservation design in the present optimization of thermal insulation characteristics and then the heating equipment is assumed to run. To optimize wall thermal insulation characteristics under the intermittent heating operation, six typically-employed walls of different thermal insulation forms were built to analyze the effect of thermal insulation forms on thermal response rate and heat flow in the inner surface comparatively. The comparative results showed that the interior insulation wall and the foamed concrete wall were the most suitable for the intermittent heating condition, while the exterior insulation wall and the self-insulation concrete wall would be relatively poor choices. The interior insulation wall and the foamed concrete wall had the highest thermal response rate and the highest surface temperature, 3 °C–10 °C higher than the other insulation wall examined, while they had the lowest values of inner surface heat flows, 26.8%–50.3% less than the other insulation wall. Keywords: Thermal response rate, Inner surface heat flow, Intermittent heating operation, Thermal insulation form