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To investigate the effects of sulfate on the properties of cementitious materials, mortar specimens with water-cement ratio of 0. 5 and 0. 35 were designed and subjected to full immersion tests to study the effects of different sulfate concentrations on the water transport properties, mechanical properties and sulfate ion transport properties of cementitious materials at different depths. The results show that the water absorption of cementitious materials after sulfate attack increases with the age of attack. The flexural and compressive strength of cementitious materials shows a trend of increasing and then decreasing with the age of sulfate attack and the concentration of attack solution. The concentration of sulfate ions increases with the increase of sulfate concentration and the concentration of sulfate ions at the same depth. The sulfate attack of cementitious materials produce swelling products to fill the internal pores and increase the mechanical properties of the specimens. [ABSTRACT FROM AUTHOR]

In order to explore the risk of spontaneous combustion of coal in the U+L type ventilation air area of the first mining surface along the roof cutting gob-side entry retaining, the engineering background of the 11101 working surface of layer 9-1# in the east area of the Mengxi Checkerboard Well Coal Mine was carried out. Through closed oxygen consumption experiments, it is determined that the oxygen consumption capacity of coal samples is weak, the oxygen consumption rate of coal samples is slow under different oxygen volume fractions, and the suffocation oxygen volume fraction(critical value of coal oxygen consumption)is 15%. The pressure difference and air leakage distribution between the two ends of roof cutting gob-side entry retaining and the working surface were determined by on-site measurement, the oxygen distribution data of the return air side was obtained by the actual measurement of the buried pipe at the site, and a similar simulation experimental bench was built for the roof cutting gob-side entry retaining in the mining area to obtain the leakage movement law of the stope. The characteristics of the leakage and spontaneous combustion oxidation distribution of the goaf area along the empty retention lane of the cut top were explored by CFD simulation, and the 3 areas of the goaf area that may have spontaneous combustion hazard were located near the open eye, close to the 5～10 m along the empty space lane and behind the working surface. Under the conditions of nitrogen injection in the tail lane and grout plugging and leak prevention and fire extinguishing measures along the boundary of the empty lane, the risk of converting the spontaneous combustion mode of the U+L ventilation air area into the spontaneous combustion mode of the U-type ventilation air area can be determined. The maximum width of the spontaneous combustion oxidation belt in the goaf area of the Checkerboard Well Mine is 80 m, the minimum safe propulsion speed is 1.2 m/d, and there is no risk of spontaneous combustion, which provides guidance for the engineering fire prevention. [ABSTRACT FROM AUTHOR]

To investigate the effects of different compressive stresses and lithium slag admixture on the chloride ion flux and gas permeability coefficient of concrete, concrete specimens with three different water-cement ratios and four lithium slag admixtures were fabricated, and 10%, 30% and 50% of the ultimate compressive load were applied to the specimens as continuous compressive stresses for chloride ion diffusivity and gas permeability tests. The results show that there is a significant correlation between the gas permeability coefficient, chloride ion flux, lithium slag admixture and compressive stress ratio of the concrete. The chloride ion flux decreases with the increase of lithium slag admixture and increases with the increase of compressive stress ratio. The gas permeation coefficient increases with the increase of lithium slag doping, and increases with the increase of compressive stress ratio. Considering the electric flux and gas permeability coefficient, the optimum dosing of C20, C30 and C40 concrete is 15%, 20% and 15% respectively. [ABSTRACT FROM AUTHOR]

The targets of carbon peak and carbon neutrality have been rapidly promoted in China since they were put forward. This arti⁃ cle systematically analyzes the challenges and opportunities faced by China to achieve these targets and discusses the areas and direc⁃ tions in which China can take actions. The analysis suggests that at this stage, China' s realization of the carbon peak and neutrality tar⁃ gets faces challenges such as high pressure concerning carbon emission reduction, tight time, high cost, insufficient technical reserves, unbalanced development, high cost of getting rid of the 'carbon lock-in', immature carbon pricing mechanism and complex interest ad⁃ justment. Meanwhile, the carbon peak and neutrality targets have created a green recovery opportunity for the low-carbon transformation of new infrastructure and traditional industries after the COVID-19 pandemic, extended the scope of ecological civilization and provid⁃ ed a systematic solution for its difficult problems. In the future, China should continue to make efforts in promoting scientific and tech⁃ nological progress, give full play to the role of carbon market and expanding green investment, boost the innovation drivers, strengthen green financial development, and deepen the construction of a community of shared future for mankind by adhering to the concept of win-win cooperation, mastering the voice of competition, and participating in global governance and cooperation from all aspects and multiple angles, so as to ensure the effective realization of the carbon peak and carbon neutrality targets. [ABSTRACT FROM AUTHOR]

Metal nanoparticles are considered as excellent catalysts in chemical reactions because of their high catalytic activity, reaction selectivity and easy preparation, but they have some disadvantages such as high cost, difficult separation, easy agglomeration, non-recycling and so on. Cellulose is by far the most abundant renewable natural polymer, which widely exists in higher plants, animals and bacteria. Because of its high specific surface area, good stability and chemical modification, cellulose-based materials can be used as a superb carrier of metal nanoparticles. In this paper, the preparation and catalytic performance of cellulose-based metal nanoparticle catalysts in recent years are reviewed, in order to provide effective methods and approaches for research. [ABSTRACT FROM AUTHOR]

Under the context of building maritime power, developing high-quality marine economy by relying on science and technology (S&T) innovation while paying attention to marine environmental protection is essential to the promotion of the sustainable development of China's marine system. This paper firstly summarizes the complex interactions between marine S&T, economy and environment from the perspective of relevance and coordination, and then constructs an integrated framework of a marine technological-economic environmental system. By constructing an indicator system, the coordinated development of the marine system in coastal areas of China is analyzed by using the coupling model and the combined prediction model. The results show that: ① The comprehensive development index of marine systems in the 11 coastal provinces sustains the growth trend from 2007 Lo 2016. The development index of three subsystem also grows significantly, while showing non-synergies in direction and degree. ② The average annual value of the coupling degree of these 11 provinces reaches 0. 74, attaining the intermediate coordination level. The technological-economic subsystem shows the largest change. With regard to the spatial difference, the coupling degree of the Bohai Rim region is the highest, followed by Yangtze River Delta region, with the Pan-Pearl River Delta being the lowest. ③ During the past 10 years, most of the marine systems among the 11 provinces have been transformed from economic-environmental coupling to technological-economic coupling, which means that the relationship between marine technology and economy is becoming closer, while the marine environment has been largely ignored. ④ Compared with the traditional scenario, the target scenario based on external expectations shows a higher degree of coupling prediction, indicating that it will be difficult to achieve sustainable requirements if the past marine development mode is continued. Therefore, it is necessary to strengthen the capacity of circulation supply in marine system, optimize the marine S&T investment and output structure, as well as implement more strict marine ecological protection policies to enhance the coordinated development of regional and national marine systems. [ABSTRACT FROM AUTHOR]

Hatu pluton in the southern margin of West Junggar invades into Early-Middle Devonian marine volcanic-sedimentary strata. The lithology of Hatu pluton is mainly composed of monzonitic granite, syenite granite and a small amount of alkali feldspar granite, which is an ideal object to study the tectonic setting of Late Carboniferous in West Junggar. The granites in Hatu pluton have high SiO2(72.06%-76.53%), Na2O+K2O(7.80%-8.57%)and Al2O3(12.55%-14.06%)contents, low CaO(0.20%-1.58%)and MgO(0.07%-0.42%)contents, with A/CNK(1.06-1.15)and A/NK(1.15-1.36)showing the characteristics of weakly peraluminous-strongly peraluminous granite. The granites have high total contents of REE((88.14-139.53)×10-6)and ratios of LREE/HREE((La/Yb)N is 3.04-6.50), and the chondrite-normalized REE pattern exhibits a typical right-dip “V” shape with a strong negative Eu anomaly, indicating that some plagioclases may be retained as a residue in the source area or there is the separation and crystallization of plagioclases. Meanwhile, the granites display significant enrichments of large ion lithophile elements(Rb, Th, U, K and Pb), relative enrichments of Zr and Hf, and depletions in Ba and Nb, especially Sr, Ti and P. The above characteristics demonstrate that Hatu pluton is a typical weakly peraluminous-strongly peraluminous A2-type granite. Combined with diagrams of major and trace elements, Hatu pluton in West Junggar is formed in a post-orogenic extension setting, and the petrogenesis is related to the juvenile crust that comprised both oceanic crust and island arc, which results from partial melting and fractionation under low pressure condition. [ABSTRACT FROM AUTHOR]

With the development of industry and agriculture, the number of degraded soil is increasing, and the situation of soil quality is severe. Soil improvement has become an urgent scientific problem and research hotspot to be solved. As an important research direction of soil improvement, rapid soil ripening technology has improved the quality and yield of crops by rapidly improving soil fertility. In this paper, based on the current situation of soil degradation, the research status, development and application of three soil ripening technologies and related joint remediation technologies at home and abroad based on physical remediation, chemical remediation, and bioremediation are summarized and expounded. The existing problems of soil [ABSTRACT FROM AUTHOR]

Ganmai Dazao Tang is a famous formula for hysteria in Jinguiyaolue(Synopsis of the Golden Chamber). The connotation of hysteria has been explored in the paper through summing up relative knowledge of medical practitioners in the successive dynasties. The pathogenesis of hysteria lies in function disorder of five viscera resulting in that five viscera fail to restrain their spirits, viscera spirits float and heart spirit is uneasy. Hysteria reflects the clinical pathological features of estrangement among qi, blood, yin and yang, and viscera spirits failing to be restrained and floating in the exterior. The combining and medicating laws of Ganmai Dazao Tang, and pathological features hysteria have been further analyzed according to principle of correspondence between formula-syndrome factors. The pharmacodynamic material basis of Ganmai Dazao Tang has been analyzed and the opinion of placebo efficacy has been negated according to the progresses in modern pharmacological research and clinical research. The combination of Ganmai Dazao Tang is rigorous, and similar to Guizhi Tang, the first one of all TCM formulas. These two formulas both are based on regulating yin and yang and widely applied in the clinic with significant curative effects. [ABSTRACT FROM AUTHOR]

The study was to investigate the effect of CA on oxidative damage, inflammatory factors and energy metabolism of H9c2 rat cardiomyocytes induced by hypoxia. H9c2 rat cardiomyocytes were divided into control group (normoxia group), hypoxia group (1% oxygen concentration) and hypoxia (1% oxygen concentration) + cichoric acid group (60 mg/L), with three replicates in each group. The results showed that compared with control group, the activity of CAT, SOD and GSH-Px, the content of anti-inflammatory factor IL-10 and the activity of energy metabolic factors Ca2+-ATPase and Na+K+-ATPase in hypoxia group were extremely decreased (P<0.01). The content of MDA, TNF-α and IL-6 in hypoxia group were extremely increased (P<0.01). The content of HO-1 was significantly decreased in hypoxia group (P<0.05). Compared with hypoxia group, the activity of GSH-Px, Ca2+-ATPase, Na+K+-ATPase and content of HO-1 in hypoxia +CA group were extremely increased (P<0.01), the activity of SOD was significantly increased (P<0.05), and the content of MDA, TNF-α and IL-6 were extremely decreased (P<0.01). The experiment indicates that CA alleviates the oxidative damage of H9c2 rat cardiomyocytes induced by hypoxia by improving the antioxidant capacity of H9c2 rat cardiomyocytes induced by hypoxia, reducing the secretion of pro-inflammatory and inflammatory factors, increasing the secretion of anti-inflammatory factors, and improving the energy metabolism level, which can improve the hypoxia adaptability of animals at high altitude. [ABSTRACT FROM AUTHOR]

The soil spectral characteristics are affected by soil particle size, water, and other factors, resulting in different spectral characteristics of soil in different regions due to different climate and geographical conditions. The soil composition prediction model established by using near-infrared spectroscopy technology often has its uniqueness. In this paper, in order to provide reference for the subsequent development of a soil nitrogen content rapid analyzer based on near-infrared spectroscopy technology, the soil nitrogen content was predicted by visible and near-infrared spectroscopy taking soil in Shanxi maize field as the research object. 120 soil samples were collected from the maize test field of Shanxi Agricultural University, and the total nitrogen content was determined and the visible and near-infrared spectroscopy was collected. The calibration set and prediction set were divided by the spectral physicochemical value co-occurrence distance(SPXY) algorithm at a ratio of 2:1. The effects of soil nitrogen content prediction models were analyzed, the models were established by combination with three modeling methods including partial least squares(PLS), support vector machine(SVM), and principal component regression(PCR), using six preprocessing methods including smoothing, standard state transformation, baseline correction, de trend, normalize, and multiple scattering correction(MSC), and the best prediction model was selected. The results showed that among the 21 prediction models established, the prediction model established by smoothing pre-processing method and PLS had the best effect, with the orientation coefficient(R2 ) of 0.907 and the prediction root mean square error(RMSEP) of 0.086. This prediction model could effectively predict the soil nitrogen content of maize fields in Shanxi province. [ABSTRACT FROM AUTHOR]