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This paper presents a systematic study on the influence of the hoop restraint effect of steel tubes on the damage evolution, ions diffusion and multi-scale mechanical properties changes in concrete specimens under the external sulfate attacks (ESA). Visual appearance, ion diffusion, dynamic modulus of elasticity and Vickers hardness were used to characterise the damage evolution, diffusion characteristics and macro/micro-mechanical changes of free/restrained expansion specimens caused by the ESA. Results indicate a lower permeation rate of sulfate ions into the matrix interior and a leaching rate of calcium ions from the matrix in the restrained expansion specimens compared with the free expansion ones. The hoop restraining stresses induced by the hoop restraint suppress the cracking of specimens, leading to a higher dynamic modulus of elasticity and Vickers hardness value in the restrained expansion specimens compared with the free expansion ones, which significantly reduces the deterioration exposed to the ESA. Hopefully, this study may offer the theoretical basis for the design of sustainable and durable concrete under the ESA.

Concerns about the durability of transportation infrastructure due to freeze–thaw (F–T) cycles are particularly significant in the Chinese plateau region, where concrete aging and performance deterioration pose substantial challenges. The current national standards for the frost resistance design of concrete structures are based predominantly on the coldest monthly average temperature and do not adequately address the comprehensive effects of the spatiotemporal variance, amplitude, and frequency of F–T cycles. To address this issue, this study introduced a spatiotemporal distribution model to analyze the long-term impact of F–T action on concrete structures by employing statistical analysis and spatial interpolation techniques. Cluster analysis was applied to create a nationwide zonation of F–T action level from data on the freezing temperature, temperature difference, and the number of F–T cycles. Furthermore, this study explored the similarity between natural environmental conditions and laboratory-accelerated tests using hydraulic pressure and cumulative damage theories. A visualization platform that incorporates tools for meteorological data queries, environmental characteristic analyses, and F–T action similarity calculations was designed. This research lays theoretical groundwork and provides technical guidance for assessing service life and enhancing the quantitative durability design of concrete structures in the Chinese plateau region.

Abstract Despite recent significant breakthroughs in novel mechanochromic luminescent (ML) materials, developing a high‐sensitivity ML material is still challengeable. Herein, a “friction‐induced crystallization” strategy is proposed to realize highly sensitive transformations of luminescent signal, through an integration of polymeric chains and an aggregation‐sensitive luminescent core, which act as mechanical sensors and fluochromic actuators, respectively. The coupling of these two components enables the material to crystallize in response to shear friction, thereby exhibiting blue‐shift fluorescence due to a more restricted relaxation pathway. This study underscores a high‐sensitivity ML material based on the precise regulation of molecular‐scale motions, and also expands the scope and potential of ML materials toward user‐friendly, interactive wearable devices.

To understand the transmissibility and spread of infectious diseases, epidemiologists turn to estimates of the instantaneous reproduction number. While many estimation approaches exist, their utility may be limited. Challenges of surveillance data collection, model assumptions that are unverifiable with data alone, and computationally inefficient frameworks are critical limitations for many existing approaches. We propose a discrete spline-based approach that solves a convex optimization problem-Poisson trend filtering-using the proximal Newton method. It produces a locally adaptive estimator for instantaneous reproduction number estimation with heterogeneous smoothness. Our methodology remains accurate even under some process misspecifications and is computationally efficient, even for large-scale data. The implementation is easily accessible in a lightweight R package rtestim.

Yield stress is an important performance parameter for cement-based materials. Nonetheless, the prediction and regulation of the yield stress using current models still requires the execution of the rheological tests at the corresponding scales (mortar or concrete), which is time-consuming and costly. This paper proposes a model for cement-based materials' (at the mortar scale) yield stress based on theoretical analysis and a multi-scale approach. This model demonstrates that mortar's yield stress can be expressed as a function of the aggregate's properties (specific surface area, volume fraction, size, and packing density) and the yield stress of a cement paste with the same water-to-cement ratio as the mortar. In addition, the model's fitting parameters are fixed for different types of aggregates. Validation tests revealed that the proposed model can accurately predict the mortar's yield stress. Finally, a relationship between relative yield stress and relative plastic viscosity is established, providing useful information for regulating the rheological properties of a given mortar.

This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam. The mechanical properties of the laboratory dam concrete, whether cured in natural or standard environments, continued to improve over time. Furthermore, the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years. However, curing and long-term exposure to the local natural environment reduced the frost resistance. Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash (FA) particles were almost fully hydrated to form compact microstructures consisting of large quantities of homogeneous calcium (alumino)silicate hydrate (C-(A)-S-H) gels and a few crystals. No obvious interfacial transition zones were observed in the microstructure owing to the long-term pozzolanic reaction. This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete. A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age. The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity, indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks. In this study, both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure, which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years. Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface. Therefore, the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution and development of its properties.

BackgroundAcetaminophen (APAP) is commonly used as an antipyretic analgesic. However, acetaminophen overdose may contribute to liver injury and even liver failure. Acetaminophen-induced liver injury (AILI) is closely related to mitochondrial oxidative stress and dysfunction, which play critical roles in cuproptosis. Here, we explored the potential role of cuproptosis-related genes (CRGs) in AILI.MethodsThe gene expression profiles were obtained from the Gene Expression Omnibus database. The differential expression of CRGs was determined between the AILI and control samples. Protein protein interaction, correlation, and functional enrichment analyses were performed. Machine learning was used to identify hub genes. Immune infiltration was evaluated. The AILI mouse model was established by intraperitoneal injection of APAP solution. Quantitative real-time PCR and western blotting were used to validate hub gene expression in the AILI mouse model. The copper content in the mouse liver samples and AML12 cells were quantified using a colorimetric assay kit. Ammonium tetrathiomolybdate (ATTM), was administered to mouse models and AML12 cells in order to investigate the effects of copper chelator on AILI.ResultsThe analysis identified 7,809 differentially expressed genes, 4,245 of which were downregulated and 3,564 of which were upregulated. Four optimal feature genes (OFGs; SDHB, PDHA1, NDUFB2, and NDUFB6) were identified through the intersection of two machine learning algorithms. Further nomogram, decision curve, and calibration curve analyses confirmed the diagnostic predictive efficacy of the four OFGs. Enrichment analysis indicated that the OFGs were involved in multiple pathways, such as IL-17 pathway and chemokine signaling pathway, that are related to AILI progression. Immune infiltration analysis revealed that macrophages were more abundant in AILI than in control samples, whereas eosinophils and endothelial cells were less abundant. Subsequently, the AILI mouse model was successfully established, and histopathological analysis using hematoxylin–eosin staining along with liver function tests revealed a significant induction of liver injury in the APAP group. Consistent with expectations, both mRNA and protein levels of the four OFGs exhibited a substantial decrease. The administration of ATTAM effectively mitigates copper elevation induced by APAP in both mouse model and AML12 cells. However, systemic administration of ATTM did not significantly alleviate AILI in the mouse model.ConclusionThis study first revealed the potential role of CRGs in the pathological process of AILI and offered novel insights into its underlying pathogenesis.

Background: Combined small cell lung cancer (C-SCLC) is a rare type of small cell lung cancer (SCLC), and it is controversial whether to choose the same treatment regimen as SCLC due to its multiple histologic components. Study methods and results: Records of patients with small cell lung cancer diagnosed between 2010 and 2020 were extracted using the SEER database. The OS of patients with different histological types under the same staging and treatment regimen was analyzed. It was found that early-stage (stage IA-IIA) surgical treatment, systemic chemotherapy alone, and chemoradiotherapy were more efficacious than C-SCLC and P-SCLC in patients with limited-stage (P = 0.054, P = 0.001, P = 0.019). In patients with extensive staging, the OS of patients with systemic chemotherapy regimens differed (P = 0.045) and was better in C-SCLC than in P-SCLC. We further explored the treatment strategy for patients with C-SCLC, which was shown by a COX regression model based on prognostic factors screened by Random Forest and LASSO regression models. Surgery, radiotherapy, and chemotherapy would be beneficial for survival. In a subgroup analysis based on stage and treatment regimen, it was shown that patients with early staging (stage IA-IIA) had a better prognosis with surgery (P

In this study, the influence of fine aggregate's grading on mortar's rheology is investigated. Firstly, the non-uniformity coefficient (Cu) and the coefficient of curvature (Cc) were employed to quantitatively evaluate the fine aggregate's grading. The results show that Cu provides a good quantitative description of the fine aggregate's grading and presents a good correlation with its packing density. Following that, the influence of the fine aggregate's grading on mortar's rheology was quantitatively analysed using the Cu parameter, and it was found that the higher the Cu value, the lower the relative yield stress (τr) and relative plastic viscosity (μr) of the corresponding mortar. In addition, the rate of variation of τr and μr with respect to Cu is very small after exceeding a critical value (4.85). This study suggests that, for a packing density higher than a critical value (0.7391), it may be more effective to improve the rheology of mortar by acting on aspects other than the fine aggregate's grading.

Under the global crisis of energy shortage and environmental pollution, the climate responsive strategies used in vernacular buildings have attracted much attention for their potential to reduce energy consumption and carbon emissions. However, the relationships between these traditional climatic strategies were not precisely perceived, which may cause the inapplicability of these strategies for contemporary rural houses. In this paper, taking the Turpan vernacular buildings in arid region of China, the climate responsive strategies of buildings in the most significant periods such as the Gaochang period (before 1318), the Khanate and Republican period (1318–1949), the Modern period (1949–2010), and the Contemporary period (2011–present) were summarized. In addition, two different types of climatic strategies organizations, namely multilayer spaces and integrated building envelopes, were identified based on the temperature difference measurement and comparative analysis. The assessment of thermal performance of the organizations was conducted by the methodology of software simulation. Furthermore, the applicability of the organizations in rural areas was discussed, and a new combined organization was proposed. Consequently, this study can contribute to provide the main approaches for climatically responsive rural houses.

Abstract The inherent quasi-brittleness of cement-based materials, due to the disorder of their hydration products and pore structures, present significant challenges for directional matrix toughening. In this work, a rigid layered skeleton of cement slurry was prepared using a simplified ice-template method, and subsequently flexible polyvinyl alcohol hydrogel was introduced into the unidirectional pores between neighboring cement platelets, resulting in the formation of a multi-layered cement-based composite. A toughness improvement of over 175 times is achieved by the implantation of such hard-soft alternatively layered microstructure. The toughening mechanism is the stretching of hydrogels at the nano-scale and deflections of micro-cracks at the interfaces, which avoid stress concentration and dissipate huge energy. Furthermore, this cement-hydrogel composite also exhibits a low thermal conductivity (around 1/10 of normal cement) and density, high specific strength and self-healing properties, which can be used in thermal insulation, seismic high-rise buildings and long-span bridges.

Concrete is the most widely used and highest-volume basic material in the word today. Enhancing its toughness, including tensile strength and deformation resistance, can boost the structural load-bearing capacity, minimize cracking, and decrease the amount of concrete and steel required in engineering projects. These advancements are crucial for the safety, durability, energy efficiency, and emission reduction of structural engineering. This paper systematically summarized the brittle characteristics of concrete and the various structural factors influencing its performance at multiple scales, including molecular, nano-micro, and meso-macro levels. It outlines the principles and impacts of concrete toughening and crack prevention from both internal and external perspectives, and discusses recent advancements and engineering applications of toughened concrete. In situ polymerization and fiber reinforcement are currently practical and highly efficient methods for enhancing concrete toughness. These techniques can boost the matrix’s flexural strength by 30% and double its fracture energy, achieving an ultimate tensile strength of up to 20 MPa and a tensile strain exceeding 0.6%. In the future, achieving breakthroughs in concrete toughening will probably rely heavily on the seamless integration and effective synergy of multi-scale toughening methods.

BackgroundLiver cancer due to hepatitis C (LCDHC) is one of the leading causes of cancer-related deaths worldwide, and the burden of LCDHC is increasing. We aimed to report the burden of LCDHC at the global, regional, and national levels in 204 countries from 1990 to 2019, stratified by etiology, sex, age, and Sociodemographic Index.MethodsData on LCDHC were available from the Global Burden of Disease, Injuries, and Risk Factors (GBD) study 2019. Numbers and age-standardized mortality, incidence, and disability-adjusted life year (DALY) rates per 100,000 population were estimated through a systematic analysis of modeled data from the GBD 2019 study. The trends in the LCDHC burden were assessed using the annual percentage change.ResultsGlobally, in 2019, there were 152,225 new cases, 141,810 deaths, and 2,878,024 DALYs due to LCDHC. From 1990 to 2019, the number of incidences, mortality, and DALY cases increased by 80.68%, 67.50%, and 37.20%, respectively. However, the age-standardized incidence, mortality, and DALY rate had a decreasing trend during this period. In 2019, the highest age-standardized incidence rates (ASIRs) of LCDHC were found in high-income Asia Pacific, North Africa and the Middle East, and Central Asia. At the regional level, Mongolia, Egypt, and Japan had the three highest ASIRs in 2019. The incidence rates of LCDHC were higher in men and increased with age, with a peak incidence in the 95+ age group for women and the 85–89 age group for men in 2019. A nonlinear association was found between the age-standardized rates of LCDHC and sociodemographic index values at the regional and national levels.ConclusionsAlthough the age-standardized rates of LCDHC have decreased, the absolute numbers of incident cases, deaths, and DALYs have increased, indicating that LCDHC remains a significant global burden. In addition, the burden of LCDHC varies geographically. Male and older adult/s individuals have a higher burden of LCDHC. Our findings provide insight into the global burden trend of LCDHC. Policymakers should establish appropriate methods to achieve the HCV elimination target by 2030 and reducing the burden of LCDHC.

AimThe objective of this study is to examine the correlation between patient serum cholinesterase (SCHE) concentration and weaning failure in the context of invasive mechanical ventilation (IMV), as well as to identify predictors of ventilator weaning failure. Additionally, this study investigates the potential relationship between SCHE and nutritional risk for developing more effective weaning strategies.MethodA retrospective observational study was conducted. The sample was collected from 227 patients with IMV over 48 h who underwent SBT before weaning. Relevant experimental samples and data collection were analyzed at the time of patient admission and before the initiation of the SBT. The correlation between SCHE and weaning failure was determined by multifactorial logistic regression and propensity matching scores.ResultsWeaning was successful in 127 patients and failed in 100 patients. Depending on the difficulty of weaning, 55 of these patients had difficulty in weaning and 45 had long-term weaning. In the crude cohort, experimental data collected on the day of SBT showed that SCHE concentrations were higher in patients with successful weaning than in those with failed weaning (4,514 u/l vs. 3,190 u/l p

The luminous environment is an essential factor that affects people’s working and living experiences in buildings. In order to clarify the building luminous environment parameters that are required for occupant satisfaction, we collected 2553 completed questionnaires while conducting field measurements of new and updated luminous comfort metrics in 15 contexts in four cities in China. By developing a five-step approach to identifying the luminous environment needs of different building occupants, including data cleaning, correlation analysis, and nonparametric testing, we determined the thresholds for all key metrics for each scenario. The research results show that different public building environments have unique luminous environment improvement requirements, and this conclusion can guide future lighting design, LED technology and daylighting integration technology.

For the intensive, efficient, and sustainable utilization of land resources, it is of great significance to optimize the spatial allocation of different types of land use intensity in rail transit station areas. The current land use optimization model has some shortcomings in objective function, constraint conditions, and the solution process. In response to this, a new multi-objective optimization model for rail transit station land use was built. With station space efficiency as the starting point, the three objectives of the model optimization were the traffic volume, environment quality, and land balance of the rail transit station, and the constraint conditions were the plot ratio, environment quality, and efficiency level. Lingo was used to solve the optimal plot ratio of different types of land use intensity. Compared with the non-inferior solution of the rail transit station area multi-objective original model, the ideal plot ratio of various land uses obtained by the optimized new model was more reasonable. There was a relatively large gap between the non-inferior solutions of some original models and the actual conditions. In contrast, the optimized new model had stronger maneuverability. The deviation ranges of the two models were −0.4% to 0.9% on the residential land plot ratio adjustment index, −3.2% to 4.8% on the public land plot ratio adjustment index, and 1.1% to 1.9% on the commercial land plot ratio adjustment index. This research aimed to provide a basis and reference for the land use and planning of Xi’an rail transit station.

The current scheme of building climate zones in China generally assumes that building climate zones of island cities are identical to adjacent land stations. Consequently, building design strategies for island buildings usually refer to those developed for inland cities. This approach has to some extent hindered the energy–saving design and green development of island buildings in China.This research takes a first step on this issue by defining the building climate zones of 36 marine islands over China marine area using two-stage zoning methodology adopted by current building climate zoning standard (GB50178-1993). The meteorological data used for analysis was obtained from the National Climate Center of China over the 30-year period from 1985 to 2014. As comparison, 40 coastal stations which are adjacent to the investigated marine islands were also included in this study. Subsequently a more objective technique—cluster analysis was operated as an effective supplement to discover the climate characteristics among different observations. The results of both methodologies consistently show that among the 36 islands investigated, the majority of islands located in northern and eastern marine area belong to the same climate zones as their adjacent coastal cities. However, island cities in southern marine area cannot be assigned to any current climate zone, which was demonstrated by its distinctive climate features different from any other sites investigated through cluster analysis as well as different energy use patterns. Thus a new zone was defined to supplement the current building climate zoning scheme to cover marine area of China.

The complex compositions and large shrinkage of concrete, as well as the strong constraints of the structures, often lead to prominent shrinkage cracking problems in modern concrete structures. This paper first introduces a multi-field (hydro–thermo–hygro–constraint) coupling model with the hydration degree of cementitious materials as the basic state parameter to estimate the shrinkage cracking risk of hardening concrete under coupling effects. Second, three new key technologies are illustrated: temperature rise inhibition, full-stage shrinkage compensation, and shrinkage reduction technologies. These technologies can efficiently reduce the thermal, autogenous, and drying shrinkages of concrete. Thereafter, a design process based on the theoretical model and key technologies is proposed to control the cracking risk index below the threshold value. Finally, two engineering application examples are provided that demonstrate that concrete shrinkage cracking can be significantly mitigated by adopting the proposed methods and technologies.

This study provides a reference for estimating the building envelope thermal performance at the initial stage of design for nearly zero-energy buildings in different climate zones. A simplified model of heat load prediction, which combines the quasi-steady-state thermal balance calculation procedure in ISO 52016 and the variable-base degree-days method, was proposed. Therefore, a building energy performance evaluation tool BPT V1.0 was developed. Subsequently, the simplified model was validated through comparative analysis with the Building Energy Simulation Test (BESTEST) standard procedure. To conduct a feasibility analysis of the development tool, case studies were performed on the performance evaluation of building envelopes of residential and office buildings in different climate zones in China. Compared to the simulation results from EnergyPlus, the deviation of heat load calculated by BPT V1.0 was within 10%, which further verifies the applicability of the tool under different climatic conditions. Annual heat load under different thermal performance building envelopes was calculated through BPT V1.0. The building energy efficiency improvement rates were found to range from 30 to 60% in nearly zero-energy buildings in different climate zones in China. The study results can provide a reference for energy managers and a basis for estimating the building energy efficiency performance with different envelope thermal properties in the region.

Hui-style architecture is a mature architectural school in the late period of ancient Chinese society with distinct regional cultural characteristics. Especially as the most direct carrier of Huizhou people’s living culture, Hui-style architecture is the witness of ancient Huizhou society, history, and culture. However, with the continuous development of society, residents gradually put forward higher requirements for the living environment. In this paper, the indoor light environment of Huizhou dwellings is measured and found to have problems such as poor indoor light environment and low light quality. In order to improve the indoor lighting quality, this study extracts the key design parameters (window edge height, window width, patio length, and patio width) that affect the indoor lighting quality through field research and literature analysis, and then uses Honeybee to carry out multi-factor orthogonal experiments and single factor quantitative comparative analyses on the key design parameters to determine the degree of influence. The results show that reducing the window edge height can improve the lighting effect near the window, and increasing the window width and patio width can improve the overall lighting quality of the room, thus providing a reference for optimizing the lighting effect of Huizhou traditional dwellings.

Optimization of insulation layer thickness is a significant factor in energy-efficient building design. Accurate determination of the thickness of the insulation layer will contribute to building energy conservation. In this study, ten typical cities in five thermal zones were selected, and the external thermal insulation of a typical residential building was taken as the research object. Using the degree day method and the economic model of full life cycle cost analysis, the optimal thickness of seven kinds of building insulation materials under absolute dry conditions, the lowest humidity and the highest humidity of the monthly average of the annual daily average were obtained. In addition, the carbon emission, energy saving and recovery period of materials under different working conditions were further obtained through numerical calculation. The results show that the optimum thickness of seven building insulation materials in ten typical cities under three working conditions is 18.21–346.05 mm. Their carbon emission change rate is between −2.7% and 38.6%, energy saving change rate is between −0.4% and 18.4%, and the payback period growth is within 1.5 years. Among them, polystyrene foam is the material least affected by humidity. It is recommended to be the main building insulation material in high humidity areas.

Improvement of geotechnical properties of soil by cementitious additives and nanomaterials is commonly used method. However, few systematic research studies on the co-effects of them on the geotechnical properties of loess have been explored. In the present research, the enhancement technique of loess was proposed based on the co-effects of graphene oxide (GO) and cement. In addition, the compactability, mechanical properties, water resistance, and microstructure of the GO/cement/loess ternary system were studied. The results revealed that, with the increase of incorporation of GO (0.03, 0.06, 0.09, and 0.12 wt. %), the optimum moisture decreased, while the dry density, mechanical properties, and water resistance increased significantly. And an optimum GO content of 0.09 wt. % was determined according to mechanical properties and water resistance. Moreover, the scanning electron microscope (SEM) results revealed that the microstructure was densified and the characteristics of pores were refined. And the co-work mechanisms of GO/cement on loess were summarized. All the results indicated that the GO/cement mixture has remarkable co-effects on the geotechnical properties of loess.

This paper proposes an optimal parking site selection scheme to alleviate CO2 emissions of the traffic flows for green urban road networks. Through the creative dynamic traffic zone programming, a constrained optimization model is set up to assess the impact of potential public parking locations on road traffic emissions. In each scenario, Thiessen Polygon based zoning method is applied to investigate the distributions of road traffics. The main contribution of this study is as follows. Firstly, this proposed model takes the CO2 emission of the whole traffic network of sustainable city development as the optimization goal, instead of the traditionally discussed travel distance or cost efficiency. Secondly, a Thiessen polygon based public parking zoning method is developed and implemented realistically. This zoning method provides a precise approach to traffic distribution and parking demand estimation. Rather than the quadrilateral or radial zoning, this method pays more attention to the parking supply demand and its impact on parking congestion. Thirdly, the genetic algorithm (GA) is used to find the optimal public parking location (PPL) sets. GA has a great application value in speeding up stochastic search for global optimization. It is especially suitable to simulate complex and large capacity problems concerning the realistic solutions. By implementing the dynamic zoning and modelling method into intelligent transportation system (ITS), the efficiency of parking induction and dynamic optimization of traffic distribution could be ensured for the future smart mobility. Therefore, this model not only serves as a novel method for public parking allocations, but hold potential to support intelligent parking guidance, as a part of the intelligent traffic system for smart city development.

A microbial transglutaminase-induced cross-linked sodium caseinate (MSC) was used to stabilize zein nanoparticles, and the study was to investigate whether zein-MSC nanoparticles (zein-MSC NPs) can be used as an encapsulation carrier for resveratrol. A group of resveratrol-loaded zein-MSC nanoparticles (Res-zein-MSC NPs) with varying zein to Res mass ratios was first prepared. The particle sizes and zeta-potentials were in the ranges from 215.00 to 225.00 nm and from −29.00 to −31.00 mV. The encapsulation efficiency (EE) of Res was also influenced by the zein to Res mass ratio, and the encapsulated Res existed in an amorphous form. The major interactions between Res and zein-MSC NPs were hydrogen bonding and hydrophobic interaction. Furthermore, compared with free Res, the photo-stability and bioaccessibility of Res-zein-MSC NPs were significantly improved. The cellular studies also showed that Res-zein-MSC NPs exhibited lower cytotoxicity and desirable anti-inflammatory activity.

This study shows the results of field measurements of an apartment building located in Tibet′s capital and in traditional houses in order to evaluate their levels concerning the living environment such as inside and outside temperature, humidity, illumination intensity, CO and CO2 concentration, intensity of solar radiation and the UV strength. The Tibetan plateau is characterized by high altitudes, low oxygen concentration, transparent atmosphere, wide diurnal range temperature, and special culture and life style, so UV and solar radiation, thermal environment and IAQ claim attention. Also a questionnaire survey was carried out for the consideration of improvements. We describe architecturally useful ways of utilizing the abundant solar energy in the Tibetan plateau of China and the solar potentials of various places are analyzed. Especially, the floor materials of the apartment houses and traditional residences in Lhasa city are examined and the living environment is improved using a direct heat gain system with simulation software. In addition, the condensation function of a solar cooker is used effectively in the local area, by selecting the most suitable materials. Also the power output performance of a solar cell using a compact portable sunlight concentrator proposes characteristic application methods for Tibetan residences.

A design scheme of multi-element sensor which included electrical resistivity probes, multiple Cl− selective electrodes, and a steel corrosion monitoring system was proposed in this work. Embedding this multi-element sensor in concrete enables the real-time and non-destructive monitoring of internal electrical resistivity, free Cl− (Clf) contents in the concrete pore solution at different depths, and steel corrosion parameters. Based on the monitoring data obtained by the multi-element sensor, the freezing-thawing (F-T) damage degree, the Clf diffusion coefficient, the quantitative relation between F-T damage degree and Clf diffusion coefficient, the initiation period of steel corrosion, and the critical content related to steel corrosion are determined. To conclude, the multi-element sensor provides key durability parameters for the establishment of the Clf diffusion model, the assessment of health condition, and the prediction of service life of concrete under the coexistence of the F-T cycle and Cl−.

This paper presents an experimental study on the flexural behavior of an innovative CA-UHPC (ultrahigh-performance concrete containing coarse aggregate) slab with high and low reinforcement ratios. A total of eighteen CA-UHPC slabs were tested to failure under the parameters of longitudinal reinforcement ratio, curing method, and maximum aggregate size. Test results indicated that sufficient longitudinal reinforcement should be embedded to prevent the brittle failure and disastrous damage. High ductile failure mode was observed for specimens with high reinforcement ratio compared with specimens with low reinforcement ratio. Instead of extensively crushing as normal strength concrete, delamination failure appeared in the compression zone of the CA-UHPC slabs owing to the fibers’ bridging effect, the yielding of longitudinal reinforcement, and the large expansion of flexural cracks which led to the final failure. The reinforced CA-UHPC slabs demonstrated excellent deformability, and ultimate ratio of deflection to span increased from 1/281 to 1/12 when the reinforcement ratio raised from 0% to 3.45%. Stiffness of the reinforced specimens at the flexural cracking state was about 88% and only approximately 6% at the ultimate state, but nearly 50% of the initial stiffness remained when the longitudinal reinforcements yielded, which indicated superior load resistance ability and excellent postcracking deformability. A new ductility index was proposed to evaluate the postcracking ductility of the CA-UHPC specimens. Finally, test results were compared with the flexural strength predictions of CECS 38-2004, ACI 544.4R, and BS EN 1992.

This study aimed to analyse the winter indoor thermal environment of double-story commercial and residential building in herdsmen settlements of China Northwest mountain grassland area. The method of research is ?eld testing and data calculation analysis; include indoor air temperature and humidity, outdoor air temperature and humidity, outdoor wind speed, thermal comfort index. The result shows the relationship between indoor thermal environment, envelope materials, heating methods, location of rooms and building type. In addition, the in?uence was quanti?ed in 0~6.9 °C in winter. Finally, put forward three strategies to enhance the winter double-story commercial and residential building indoor environment.

In the past several decades, many literatures have emerged on the topic of phase change material and latent heat storage techniques used in building. Accordingly, it is essential to review previous work to know about phase change material application in building better. This article presents a review on phase change material application situations in building, and several aspects are discussed: phase change material major applications in building, phase change material application areas, phase change material application types, phase change material thermal–physical properties, and phase change material application effects. The results of this research show that phase change material application areas are mainly concentrated into four parts of north latitude from 25° to 60° and south latitude from 25° to 40°. No matter in which region, the use of paraffin is the broadest (the maximum use frequency is up to 87.5%). For organic phase change material, the melting temperature and the heat of fusion vary from 19°C to 29°C and from 120 kJ/kg to 280 kJ/kg, respectively. The best phase change material application effect found is a reduction of 4.2°C for air temperature in room. This study has important and directive significance for the practical application of phase change material in building.

In regions with abundant solar energy, building walls facing different directions absorb very different amounts of solar energy. These differences should be considered in thermal insulation design, unlike the current design standard in China, which does not take directionality into account when calculating the limit value of the heat transfer coefficient of building envelope. To address this short-coming, this article proposes a generalized non-balanced thermal insulation system for the building envelope: walls receiving greater amounts of solar energy should have less insulation, while walls receiving less amounts of solar energy should have more insulation. By analysis of outdoor synthetic temperatures for different orientations, non-balanced heat transfer coefficients are calculated under a constant heat flux condition. Considering the Lhasa region as a case study, the testing of an indoor thermal environment in winter was conducted, and a novel non-balanced thermal insulation system was built. The internal surface temperature of the external walls under two types of heat transfer coefficient limit values and the frequency responses of the two types of thermal insulation wall constructions are analyzed using the wall thermal theoretical method. The results show that this new thermal insulation design can make better use of solar energy, thus reducing conventional heating. This article provides a theoretical reference for the future design of non-balanced thermal insulation systems for building envelope and also provides a theoretical calculation method for the part of building envelope thermal design in the national standard of the People’s Republic China (Thermal Design Code for Civil Building-GB50176).

China is actively promoting ocean territory construction, and how to design low-energy buildings to fit the unique climate of tropical island regions has received much attention. The heat transfer coefficient of a building external surface plays a vital role in calculating air-conditioning load accurately. To obtain reasonable heat transfer coefficients in the tropical island region, this study introduced a naphthalene sublimation experiment to conduct full-scale measurements on convective heat transfer coefficients (CHTCs) in the tropical island region, and proposed a simplified calculation model of evaporative heat transfer coefficients (EHTCs). Results indicated that the function expression between CHTC and wind speed was CHTC = 5.56 + 4.48u (R2 = 0.94), and it was validated to be reliable. Furthermore, compared with CHTCs and radiation heat transfer coefficients (RHTCs), the EHTC had a wider changing range, owing to rainfall effects. Moreover, whether evaporation was considered or not, the difference of total heat transfer coefficients (THTCs) on building external surfaces was 5.2 W/(m2·K) for the whole year, so evaporation cannot be ignored directly. Additionally, THTCs with consideration of evaporation in winter and summer were 33.4 W/(m2·K) and 38.9 W/(m2·K) severally, which are much larger than the recommended values in the Chinese standard. This study would make up for the lack of surface heat transfer coefficients in energy conservation design of tropical island buildings.

It is generally accepted that fine particles could accelerate cement hydration process, or, more specifically, this accelerating effect can be attributed to additional surface area introduced by fine particles. In addition to this view, the surface state of fine particles is also an important factor, especially for nanoparticles. In the previous study, a series of nano-SiO2-polycarboxylate superplasticizer core-shell nanoparticles (NS@PCE) were synthesized, which have a similar particle size distribution but different surface properties. In this study, the impact of NS@PCE on cement hydration was investigated by heat flow calorimetry, mechanical property measurement, XRD, and SEM. Results show that, among a series of NS@PCE, NS@PCE-2 with a moderate shell-core ratio appeared to be more effective in accelerating cement hydration. As dosage increases, the efficiency of NS@PCE-2 would reach a plateau which is quantified by various characteristic values. Compressive strength results indicate that strength has a linear correlation with cumulative heat release. A hypothesis was proposed to explain the modification effect of NS@PCE, which highlights a balance between initial dispersion and pozzolanic reactivity. This paper provides a new understanding for the surface modification of supplementary cementitious materials and their application and also sheds a new light on nano-SiO2 for optimizing cement-based materials.

The effect of expanded polystyrene (EPS) inclusions on thermal conductivity of lightweight concrete is studied. Various mixtures are produced by incorporating EPS aggregate at different volumes (0%, 10%, 20%, 30% and 40%) in concrete with three water/cement ratios (0.55, 0.50 and 0.45). The apparent density and thermal conductivity values of expanded polystyrene concrete decrease as the volume of EPS increases. The thermal conductivity increases with an exponential function of the apparent density whatever the water/cement ratios. The general thermal conductivity models can not well predict the present experimental results. Based on experimental results and composite approach, a new simplified model is proposed to evaluate the effective thermal conductivity with an equation of the plain concrete thermal conductivity, the EPS thermal conductivity, the density and the percentage of EPS particles. The model is applicable to the EPS lightweight concretes with different water and cement ratios.

In recent years the piston effect in subways has become a topic of interest for researchers and engineers. Many publications have appeared on this topic, but reliable information is scattered and poorly organized. This review paper covers the latest publications on the piston effect in subways. We compile information about the mechanism of the piston effect, evaluate its influence, and describe how it can be effectively utilized.

There is no standard testing method of the thermal physical properties of phase change materials (PCM). This paper has shown advancements in this field. Developments and achievements in thermal physical properties testing methods of PCM were commented, including differential scanning calorimetry, T-history measurement, the water bath method, and differential thermal analysis. Testing principles, advantages and disadvantages, and important points for attention of each method were discussed. A foundation for standardized testing methods for PCM was made.

The flow-field characteristics of high-temperature annular buoyant jets as well as the development laws influenced by ventilation system were studied using numerical methods to eliminate the pollutants effectively in this paper. The development laws of high-temperature annular buoyant jets were analyzed and compared with previous studies, including radial velocity distribution, axial velocity and temperature decay, reattachment position, cross-section diameter, volumetric flow rate, and velocity field characteristics with different pressures at the exhaust hood inlet. The results showed that when the ratio of outer diameter to inner diameter of the annulus was smaller than 5/2, the flow-field characteristics had significant difference compared to circular buoyant jets with the same outer diameter. For similar diameter ratios, reattachment in this paper occurred further downstream in contrast to previous study. Besides, the development laws of volumetric flow rate and cross-section diameter were given with different initial parameters. In addition, through analyzing air distribution characteristics under the coupling effect of high-temperature annular buoyant jets and ventilation system, it could be found that the position where maximum axial velocity occurred was changing gradually when the pressure at the exhaust hood inlet changed from 0 Pa to −5 Pa.

The climate in China varies substantially across its extensive territory. However, the traditional thermal design of buildings is primarily based on pure heat calculation that considers only heat transfer. Therefore, the heat transfer of a building envelope should be clarified under the action of periodic external disturbance circulation. In this study, four different climatic factors were selected for heat transfer simulation, including season, solar radiation, air temperature, and relative humidity. The results indicate that the outdoor relative humidity has a significant impact on the difference between coupled heat and moisture calculation and pure thermal calculation. This influence becomes evident in the cooling conditions in summer but weakens in the winter heating conditions. Accordingly, the meteorological data of 270 cities in China were statistically analyzed using Python programming language. The concept of “cooling high-humidity days” was proposed as a zoning indicator for coupled heat and humidity thermal calculation zoning. The coupled heat and moisture thermal calculation design zoning map of China is provided, which affords the specific calculation method in building thermal design. [ABSTRACT FROM AUTHOR]