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Ordinary Portland cement (OPC) is proving to be hazardous to the environment. To replace the OPC, geopolymers (GPs) are introduced. However, to fully replace the OPC by GPs extensive laboratory tests are required to assess the long-term and short-term properties of GPs in different scenarios. Given the shortage of time for performing such extensive testing, artificial intelligence (AI) is used to analyze the properties of GPs. In this study, different AI techniques such as artificial neuro network (ANN), adaptive neuro-fuzzy inference system (ANFIS), and gene expression programming (GEP) are used to obtain the predictive models for estimating the compressive strength of fly ash and ground granulated blast furnace slag-based GP concrete. Different statistical parameters are used to evaluate the performance of predictive models. Similarly, sensitivity and parametric analysis are also conducted on the input parameters. Additionally, multiple linear regression was also performed on the whole database. After comparing all the results, it was concluded that GEP is the best AI technique to predict the compressive strength of GP-based concrete.

High quality marine natural resource management cannot be achieved without the support of data and information. Given the unique nature of marine data, the processing of marine environmental data often involves long time series or large-scale processing work. For data processing work mainly focused on intensive computing, universal cloud platforms have prominent issues of low efficiency. Based on a comprehensive analysis of the native resource scheduling algorithms on the Hadoop platform and the characteristics of intensive computing in ocean data processing, this paper innovatively proposes a genetic algorithm task scheduling strategy based on a competitive model. The use of chaotic algorithm mechanism as the basis for genetic algorithm population initialization ensures that the solution space obtained during each initialization can be uniformly distributed, effectively solving the problem of genetic algorithm solving speed being greatly affected by the initialization population and population evolution measurement. In addition, in order to speed up rate of convergence, competition mechanism is introduced and an adaptive evolution model based on population competition is proposed. Through the actual verification and comparison of the built models, it is proved that the improved algorithm is superior to the traditional genetic algorithm in rate of convergence and stability of the convergence results, and has greatly improved the ability and efficiency of improving the resource scheduling of the ocean cloud platform.

The China Geological Survey (CGS) has carried out a large number of surveys and core drilling over the deepwater area of Qiongdongnan Basin (QDNB) in the South China Sea and discovered the natural gas hydrate system controlled by the gas chimney with a high geothermal gradient. The complex hydrate system consists of a sandy hydrate reservoir distributed around a lateral transition gas-hydrate mixed zone and a free gas zone in the middle. The hydrate and gas are distributed in the same layer, which is thin but potentially valuable for commercial exploitation. In this paper, a geological model of the target hydrate system in QDNB was established based on the results of several rounds of drilling. The method of numerical simulation was utilized to assess the production capacity of the target hydrate system and clarify the evolution of hydrate and gas saturation distribution with different well positions. The simulation results indicate that the producer well built in the center of the highly-saturated hydrate zone has a limited gas production capacity, with a cumulative production of only 7.25 × 106 m3 in 9 years. The well built at the boundary of the hydrate zone can rapidly link up the gas in the transition zone through a large production pressure differential, but it lacks control over the hydrates and its dissociated gas in the transition zone—the cumulative gas production volume from hydrate accounts for only 12.3%. As for the wells built in the transition zone and gas zone, they can directly invoke the free gas production capacity. Free gas is produced as the formation pressure reduces and hydrate is induced to dissociate, making the gas from the hydrate the subsequent production capacity. The cumulative production can exceed 6 × 108 m3 in 9 years. The stable production duration can extend to 2645 days, and the cumulative proportion of gas at the wellhead from hydrate reaches close to 30%. It is necessary to avoid the free water layer. The bottom water coning would improve the water production by 40% and shorten the stable production duration. In summary, the complex hydrate system of this type in the QDNB has the potential for industrialized exploitation. In the future, the well group can be used for the further improvement of the hydrate utilization rate.

It is evident that zinc supplementation is essential for maintaining good health and preventing disease. In this study, a novel oyster peptide–zinc complex with an average molecular weight of 500 Da was prepared from oyster meat and purified using ultrafiltration, ultrasound, a programmed cooling procedure, chelating, and dialysis. The optimal chelating process parameters obtained through a response surface methodology optimization design are a peptide/zinc ratio of 15, pH of 6.53, reaction time of 80 min, and peptide concentration of 0.06 g/mL. Then, the structure of a peptide–zinc complex (named COP2-Zn) was investigated using the UV and infrared spectrums. The results showed that the maximum absorption peak was redshifted from 224.5 nm to 228.3 nm and the main difference of the absorption peaks was 1396.4 cm−1. The cytotoxicity and antiproliferative effects of COP2-Zn were evaluated. The results showed that COP2-Zn had a better antiproliferative effect than the unchelated peptide against HepG2 cells. A DNA flow cytometric analysis showed that COP2-Zn induced S-phase arrest in HepG2 cells in a dose-dependent manner. Additionally, the flow cytometer indicated that COP2-Zn significantly induced HepG2 cell apoptosis.

To reduce the structural deterioration of mass concrete structures from temperature cracks, and lower energy consumption caused by the traditional mass concrete hydration heat cooling process, this paper reports the preparation of concrete temperature-controlled phase change aggregate (PCA) by a vacuum compaction method using light and high-strength black ceramite and No. 58 fully refined paraffin wax as phase change material (PCM), and the encapsulation technology of the aggregate by using superfine cement and epoxy resin. Further, through laboratory tests, the cylinder compressive strength, thermal stability and mixing breakage rate of the encapsulated PCA were tested, and the differences in mechanical properties such as compressive strength, flexural strength and splitting tensile strength between phase change aggregate concrete (PCAC) and ordinary concrete were studied. A test method was designed to test the heat storage effect of PCA, and the temperature control effect of PCAC was analyzed based on the law of conservation of energy. The research conclusions are as follows: (1) Both superfine cement and epoxy resin shells increase the strength of the aggregate, with the epoxy resin increasing it more than the superfine cement. The thermal stabilization of the PCA is good after encapsulation of superfine cement and epoxy resin. However, PCA encapsulated in superfine cement is more easily crushed than that encapsulated in epoxy resin. (2) Under the condition of water bath heating and semi-insulation, when the water bath temperature reaches 85 °C, the temperature difference between the PCA and the common stone aggregate can be up to 6 °C. Based on the law of energy conservation, the test results will be converted to mass concrete with the same volume of aggregate mixture;, the difference of PCAC and ordinary concrete temperature can be up to 10 °C, so the temperature control effect is significant. (3) The mechanical properties of PCAC with 100% aggregate replacement rate compared to ordinary concrete are reduced to varying degrees, and the performance decline of the epoxy-encapsulated PCA is smaller than that encapsulated with superfine cement; in an actual project, it is possible to improve the concrete grade to make up for this defect.