Table of contents

2021 7th International Conference on Environment and Renewable Energy (ICERE 2021) was supposed to be held during March 26-28, 2021, Qingdao, China.

Almost all countries have travel restrictions due to COVID-19 pandemic. Now, the situation of COVID-19 pandemic is unpredictable around the world. Most of countries are still fighting the COVID-19 pandemic, so it is inadvisable to postpone the conference. Taking all conditions into consideration, conference committees made a tough decision to change physical conference into virtual format conference. Conference participants can't go to the conference venue and do oral presentations, it is feasible to have virtual format conference. We use zoom application which makes virtual format conference come true. ICERE 2021 was dedicated to issues related to Environment and Renewable Energy.

List of Committees, Conference Co-Chairs, International Technical Committee are available in this pdf.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

• Type of peer review:

Double-blind

• Conference submission management system:

Iconf submission system

• Number of submissions received:

39 papers

• Number of submissions sent for review:

39 papers

• Number of submissions accepted:

20 papers

• Acceptance Rate (Number of Submissions Accepted/Number of Submissions Received X 100):

51.28%

• Average number of reviews per paper:

2 papers

• Total number of reviewers involved:

10 reviewers

• Any additional info on review process:

1. Preliminary Review

When we received authors' paper(abstract and full paper), we will submit the paper to auditing department for checking, the auditing department will review the content, format and grammers.

2. The full papers passed the first review will be eviewed again by conference technical committees from the following aspects: Originality, Innovation, Technical Soundness, Applicability, Clarity of presentation and Relevance.

3. Only the paper passed the first review and the second review, it can be published.

• Contact person for queries:

Prof. Gordon Huang

University of Regina, Canada

Beijing Normal University, China

guohe.huang@outlook.com

The biggest part of the energy consumption of buildings is for thermal comfort. Awareness on climate change and concerns about the depletion of natural resources made the necessity to use renewable energy sources in buildings evident. In this context, microalgae have high surface efficiency and consume inorganic carbon, thus enabling carbon-neutral operation. They can be integrated into building façades with photobioreactors to reduce energy demands. This paper aims to clarify and discuss the role of microalgal technologies in energy-efficient architecture. The thermal performance and energy generation properties of microalgae façades are comprehensively reviewed. The results show that microalgae provide dynamic shading and thermal insulation, thus have the potential to significantly reduce the thermal load and energy demands of buildings and increase the building performance. Consequently, besides the thermal performance of microalgae façades, evaluation of daylight, lighting, environmental and cost performance, technical applicability and aesthetics are necessary.

Passive house concept, which has been widely developed globally, is still in its infancy in the hot summer cold winter zone (HSCW) in China. This paper made a climatic condition comparison among the HSCW zone, cold zone and German. In addition, 23 passive house projects were selected as cases for analysing, concerning thermal characteristic and building performance. The findings show that building a passive house in HSCW zone can not simply following the basic passive house principles from the Passive House Institute, and several indicators should be modified.

With the rapid growth of aging population in China, researchers have paid more attention to the aging planning and architectural design of elderly community. As the particularity of elderly people, they have higher demand on the comfort and safety of the outdoor wind environment, and the outdoor vegetation system has a great contribution on improving outdoor wind environment which has been proved. In this study, the influence of vegetation system on outdoor wind environment in extreme weather of a nursing home has been quantitatively investigated according to CFD methods. The parameters related to the wind environment including average wind velocity and its distribution has been calculated. Results showed that vegetation system could improve the outdoor wind environment significantly, especially planting shrub and grass. After planting deciduous and evergreen arbors, shrub and grass, the average wind velocities of all the living and activity regions decreased below to 1.5m/s, and area proportion of the regions with low wind velocity increased up to 75%.

There is paucity of environmental data for Orani river systems in Bataan (Philippines) despite its regional economic and ecological significance. The present study conducted multivariate analyses of various water quality parameters and selected bacterial communities to evaluate the river's health integrity. River data exhibited spatial and seasonal variation, with observed significantly distinct heterotrophic and Gram-negative bacterial counts in the midstream and downstream against upstream samples. Fecal coliform concentrations were statistically different in the sequence: upstream < downstream < midstream. Multivariate Principal Component Analysis identified the most important variables affecting the variability in bacterial concentrations among the sampling groups (81.64% variation). Cluster analysis also revealed the associations and similarities of sampling groups based on abundance of bacterial loadings. Further, water quality indices were classified within "marginal" class (54.77 for wet season; 57.67 for dry season). The hydrological index estimated a score of 47.97 for wet season that described as "suitable with high restriction" class (30<(HI)c<55), and 62.24 for dry season in the "suitable with medium restriction" class (55<(HI)c<75).

In recent years, air pollution in China is becoming more and more serious. Due to air pollution, people were forced to wear masks on streets and some schools even suspended their classes. Many researches had proved that air pollution will cause severe damages to human health. This research focused on reviewing the previous studies on the air pollution's effects on Chinese children, adolescents, & young adults (the target population), and tried to provide suggestions for future research. The previous researches conducted on this topic were searched on cnki.net and Pubmed and collected. The obtained papers are selected and analyzed. It can be concluded that air pollution had huge effects on the target population's respiratory system, cardiovascular system, and mental state.

The ecological problems brought by the rapid development of the economy and society have threatened humanity's sustainable development. As the world's largest carbon emitter, China is still at a critical stage of industrialization, and it is urgent to solve the problem of how to realize the low-carbon circular development of the economy. This paper constructed the evaluation index system of regional low carbon development from the three dimensions of development, low carbon, and ecology. Based on the entropy weight-TOPSIS model, the index was quantitatively analyzed with the data of 30 provinces in China in 2018. According to the measurement results, 30 provinces, were clustered into low-carbon development zones, relatively low-carbon development zones, relatively high-carbon development zones, and high-carbon development zones according to the low-carbon ecological development level. The results show that China's overall low-carbon economic development level is not high in 2018, with the south being superior to the north, and the eastern coastal areas of Guangdong, Jiangsu, Shandong, and Zhejiang being significantly prime to other regions. Finally, suggestions are given for different types of low-carbon development areas.

The study was carried out to validate the effect of different flush induction protocol on carabao mango which was conducted in Alion, Mariveles, Bataan, Philippines with the following treatments: no intervention (T₁), pruning only (T₂), pruning with urea applied in soil (T₃), pruning with urea spray (T₄), pruning with irrigation (T₅), and complete flush induction protocol (T₆). Results revealed that providing water hasten the flush induction of mango. The complete flush induction protocol (T₆) significantly had the highest flushing percentage and the longest flushing duration. In terms of leaf produced per flush, pruning alone (T₂) and pruning with urea spray (T₄) equally produced the highest number of leaves per flush having 16 leaves. On the other hand, different flush induction protocols have no direct effect on flush and stem length, stem diameter, flush dry weight, and in the amount of nutrients in the flushes except for total amount of iron.

Based on the tropical cyclone data of the United States Joint Typhoon Center, this paper analyses the characteristics of the temporal and spatial changes of tropical cyclones that landed in China from 1951 to 2015. The conclusions are as follows: (1) The frequency of landings showed a slow upward trend from 1951 to the early 1990s, and showed a slow downward trend from the late 1990s to 2015. In 1988, it changed from a low period to a high period. (2) Tropical cyclones are mainly distributed in the range of 130-140°E, 10-15°N east of the Philippine Islands, and the northeastern part of the South China Sea. The spatial distribution of the first eigenvector of the source frequency EOF is basically the same as the multi-year spatial distribution. From the time coefficient of the first mode, the change trend of the concentrated distribution has undergone a process of strengthening-weakening. From the perspective of the spatial distribution of the second mode, the source frequencies in the Northwest Pacific and the South China Sea have opposite spatial distribution characteristics in the latitude direction. (3) One of the main tracks of landfall tropical cyclones is westward from the tropical Pacific to the Philippine Sea and South China Sea, and the other from the tropical Pacific to the northwest to South Korea and Japan, affecting the area near the coast of East Asia. The spatial distribution of the first eigenvector of the track frequency EOF is basically the same as that of the multi-year spatial distribution, and the spatial distribution of the second mode has a positive-negative opposite spatial distribution characteristic in the meridian direction.

This paper deals with methane hydrate formation from SDS solution of 0.1 wt% in reactor with cooling spiral. Intensity of methane hydrate formation process in a vertical and horizontal cylindrical reactor with a cooled spiral at three fixed volumes of a surfactant solution was compared. The dependence of the gas content of the obtained samples depending on volume of the liquid phase and on the position of the reactor was revealed. The hypotheses about influence of diffusion at the interface and capillary effect on the cooled element on the gas content were examined. Also the efficiency of gas supply mode was tested. The best result for gas consumption in single gas injection mode is 60,21 L•L^–1 achieved with a liquid volume of 300 ml in a vertical reactor. The best result for gas consumption in constant gas supply mode is 161,3 L•L^–1 achieved with a liquid volume of 500 ml in a horizontal reactor.

Production of high quality product gas via biomass steam gasification is a promising technology. However, impurities in the product gas, namely tars, cause problems in the downstream gas processing operations and thus they need to be removed efficiently. Oil scrubbing is an effective solution for tar removal due to its non-polar characteristic which is similar to tar nature. In this research, solubility values of five simulated tar compounds were experimentally investigated for selecting the new scrubbing solvent. The simulated tar compounds investigated represent those found in the dual fluidized bed steam gasification of wood biomass, which are: naphthalene, biphenyl, anthracene, fluoranthene, and pyrene. The scrubbing solvents tested in this research are classified into biodiesels, vegetable oils, and diesel. Biodiesel used are rapeseed methyl ester (RME) and 2 different palm methyl esters (denoted as PME1 and PME2). Vegetable oils are sunflower oil, refined palm oil, Thai rice bran oil, and crude palm oil. All of the solubility tests were performed in the laboratory-scale test-rig at 30, 50, 70, and 80°C. Biodiesels are found to be the effective solvent in dissolving the tar compounds. PME1 shows the similar tar removal performance to RME but is more readily available; therefore, PME1 is chosen to be used as a scrubbing solvent at the Thailand 1 MWel prototype DFB gasifier at Nong Bua district in Nakhon Sawan province, Thailand.

The integration of algae-based wastewater treatment and biofuel production has been of growing research interest in recent years. This article reviewed recent researches in algae biofuel production and the integration of algal wastewater treatment and biofuel production. The methods to algal biofuel production, biofuel productivity, and removal rate of treated municipal wastewater were summarized in this review. Chlorella is largely used, especially in biodiesel and bioethanol production. Spirulina is more often used to produce biogas. The removal rate of NH4+-N can be high in this integration. The most common biofuel products in this integration are biomethane and lipid. Traces of the integration are numerous on laboratory basis and limited in commercial use for now. The barrier to apply it from lab to commercial use may include a high cost during algae harvesting as well as land use and availability. Possible solutions and research gaps are outlined in this article.

Solid-state battery is different from traditional lithium-ion battery, which is a kind of battery using solid electrode and solid electrolyte, and it has the advantages of high safety, long life, high charging and discharging efficiency, good high temperature resistance, simple assembly and processing, and easy to scale up. This paper first analyzes the industrial chain of solid-state batteries in China and the stakeholders in the process of industrial development, and finally draws a technology roadmap for the development of China's solid-state battery industry based on industrial characteristics. In the future, along with energy transformation and national policy support, the focus should be on solid state electrolytes for solid state batteries, and gradually realize the development path of solid state battery electrolytes from liquid state of traditional lithium-ion batteries to solid-liquid hybrid, gel, solid state, and all-solid state.

with the development of economy and the reform of cities, the bridge engineering in China has entered a period of rapid development. By 2009, the number of highway bridges in China has exceeded that of the rest of the world. According to the statistics of 2014, the number of roads and bridges in China is 757100, and its extension meters reach 42.5789 million. The emergence of BIM technology has brought a new experience to China's construction industry. Compared with the traditional CAD, the most significant change in BIM technology is to change building information from two-dimensional to three-dimensional. At the same time, BIM visualization, synergy and automation help building participants to do a lot of work better and more conveniently. Because of the continuous expansion of bridge engineering in China, bridge engineering has gradually become more complex and diverse, which has also brought problems to many industries. The research on BIM in our country is still in some surface stages. There are deeper things worth digging into.

In recent years, BIM technology has developed rapidly in the field of housing construction, and has been well applied in many housing construction projects. However, the application of BIM technology on bridges is less. This article takes Hongjiazhong Bridge as an example to research and explore the application of BIM technology in bridges. Conduct application research on accountability, program simulation, quality and safety management, BIM platform management, etc., and explain the innovative applications of BIM technology in GIS, VR, AR, operation and maintenance.

This paper presents the development of new concrete mixtures, which constitutes prefabricated elements for building constructions in tropical conditions in Gabon (Africa). The Client from Gabon required prefabricated buildings fabricated overseas (in Serbia) and assembled at the site (Okolassi, Gabon). The main problem was to achieve sufficient strength and resistance of finishing material, with small weight. New material was developed in order to satisfy the following conditions: low unit weight, high compressive/tensile strength, low shrinkage, reduced spalling, resistance to high temperatures and moisture. The main need for development of these new concrete mixtures lies in characteristics of designed prefabricated concrete elements, with the following main properties: a) concrete panels, with dimensions 240-360 cm (length), 110 cm (height), and 20 cm (width); b) panels should weigh up to 100 kg/pc, but sound and robust, so surface must be casted of ultra-high-performance concrete, while the inner part of the element should have smaller unit weight. New concrete mixtures with the required properties were designed on the basis of the extensive laboratory analysis. Concrete specimens were prepared using the materials available at the market and tested. Testing results were further analysed in order to derive convenient mathematical models for the target concrete properties. The results of this analysis were new concrete mixtures, prepared according to the derived models, to be used for construction of prefabricated concrete panels.

This research work focuses on investigating the fatigue and thermal cracking resistance of asphalt binder with different percentages of styrene-butadiene-styrene (SBS) utilizing rheological testing methods. The laboratory experimental program includes the Dynamic Shear Rheometer (DSR) test at intermediate temperature for fatigue cracking and Bending Beam Rheometer (BBR) at low temperature to assess thermal cracking. The polymer-modified asphalt binders were prepared using four different SBS contents of 2.5, 4.2, 4.8, and 6.1% by asphalt binder weight. The test results were then used to compare the performance of four different SBS modified binders and the control asphalt binder without SBS. The findings showed that the addition of the SBS to asphalt binder improved the fatigue resistance as it was noted that the fatigue parameter (G*.sin δ) was decreasing as the temperature decreases. The BBR results also showed that the addition of SBS enhanced the low-temperature performance by lowing the creep stiffness and increasing the m-values compared to the control asphalt binder. The best performance against fatigue cracking and thermal cracking was obtained using 6.1% SBS.

For the purpose of investigating the influence of fine contents on the dynamic properties of mixed soil, a series of triaxial tests were conducted on the gravelly soil mixed with fine contents. The confining pressures of 100, 150, and 200 kPa were selected. The dynamic triaxial tests were carried out on the samples with 0%, 20%, and 40% fine contents respectively. The axial dynamic strain and pore water pressure curves of the specimens were obtained when different excitation forces were applied. The experimental results indicated that the strength of mixed soils presented an increasing tendency with the increase of confining pressures. Under low confining pressure, the strength increased at first then decreased with the increase of fine contents, while appearing to downtrend under high confining pressure. When the excitation force was large, the axial dynamic strain and pore water pressure increased rapidly.

In recent years, an increase in extreme rainfall events linked to global warming has led to increases in the number and intensity of disasters such as landslides, landslips, and debris flows in Taiwan. This study focuses on the impact of such events, especially during typhoons, on County Road 89: the main traffic artery in Renai Township, Nantou County. Specifically, it will use an inverse distance weighting method (IDW) to analyze how rainfall at the four rainfall stations in Nantou, located at Renai, Ruiyan, Cuiluan and Cuihua, may related to damage events at the 12.3k, 22.53k, 32.5k, 46.3k, and 49k points on County Road 89. Then, landslide road-damage warning ranges will be drawn up using various combinations of data, including cumulative rainfall, maximum rainfall within a 24-hour period, and I-R alert model (I: rainfall intensity, R: cumulative rainfall), with an I-T alert model (I: rainfall intensity, T: rainfall duration) for comparison. This will yield an optimal warning value for the landslide-prone area of the focal road. Finally, data from County Road 89 will be compared against data from the Lishan landslide area, to ascertain whether/how such warning values should differ across geographic areas. The results are expected to usefully inform follow-up disaster prevention planning as well as further academic research on this topic.

As an important way to relieve the traffic pressure across rivers, immersed tunnel engineering has been gradually promoted. This paper introduces building information modeling and virtual reality technology into immersed tunnel engineering, analyzes its technical characteristics and advantages, expounds the application of BIM + VR technology in immersed tunnel engineering, and carries out practice in immersed tunnel engineering of Shenzhen-Zhongshan Bridge, which verifies the superiority and efficiency of the method.

Over the past several years all European capitals have been dealing with traffic-related problems, the harmful influence of passenger transport on the environment, and the necessity to adopt measures for achieving sustainable urban mobility. The dynamic development of the city of Sofia in recent years has led to an increased number of personal vehicles, air pollution, and the necessity for servicing large passenger flows effectively and relieving traffic in the city's center. The global practice is to solve urban mobility transport problems in larger cities with a population of over one million by developing a subway system which should become the primary mode of urban passenger transport, securing quick access to work places, guaranteeing high-quality, safe and secure travel, while simultaneously minimizing pollution, greenhouse effects and energy consumption. The purpose of the present article is to substantiate the necessity for finishing the construction of the capital's subway system, to indicate the social benefits of the functioning of the first and second subway lines in the context of sustainable urban mobility, and to prognosticate the future social benefits of constructing and commissioning the third subway diameter through analysis of the dynamic of the city's public transport and the available statistical data.