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The rapid and efficient elimination of CO by-products in mining and tunneling blasting operations poses a significant challenge. In this study, an in-situ synchronous elimination method (ISSE) for CO was proposed based on catalytic oxidation principles by deploying nano-scale catalysts in boreholes. Initially, Co 3 O 4 catalyst was prepared and characterized. Subsequently, the catalyst was processed into a packing bag for in-situ CO elimination within boreholes. Field experiments were conducted at the Lujiatuo coal mine to verify the ISSE technology, and the effects of packaging materials, charging configuration, catalyst concentration, and length-to-diameter ratio of the packing bag on CO elimination efficiency were investigated. The experimental results revealed that when utilizing a nylon water cannon mud bag and charging 35 g of catalyst at the orifice, the peak CO concentration decreased from 735 ppm to 243 ppm, achieving an elimination efficiency of 66.9 % and reducing CO exceedance time by 28.5 %. These findings indicate that the ISSE technology surpasses existing techniques in terms of CO eliminating during mining and tunneling operations rapidly and effectively, that are expected to find widespread application in blasting production. [Display omitted] • An in-situ synchronous elimination (ISSE) method is proposed. • The influencing factors of ISSE method has been investigated. • The CO elimination rate achieved 66.9 % in field tests. [ABSTRACT FROM AUTHOR]

Global biodiversity conservation has recently focused on the roles of land management strategies of land sharing vs. land sparing. However, few studies have evaluated the roles of social and ecological interactions in modifying the effectiveness of land management for top predator conservation. Using a 65-year dataset from northeastern China, we evaluated the roles of government social policies in resolving human-wildlife conflicts and improving human livelihood. From 1998 to 2015, both big cat populations and their habitats have increased. Concurrently, regional human population density decreased by 59.6%, forest volume logged was reduced by 62.6%. Consequently, increases of key prey species were observed during the same periods. Although populations remained small, the annual finite rate of increase was 1.04 for the Amur tiger population and 1.08 for Amur leopards from 1999 to 2015. Habitat areas occupied by big cats increased significantly. Overexploitation of forest resources and big cat declines under previous unsustainable land use are progressively being reversed under land sparing. Large economic investment and intense human-relocation projects coupled with efforts to reduce poaching and illegal hunting and trapping demonstrate a complex social and ecological synergy in big cat conservation in China. [ABSTRACT FROM AUTHOR]

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Abstract: Prescribed fire and herbicide are silvicultural tools that influence biodiversity in intensively managed, mid-rotation pine (Pinus spp.) stands. These forest types are common in the southeastern United States and are economically and ecologically important. Understanding biodiversity responses to silvicultural treatments is important to fully understand management approaches to maintain sustainability of forestry practices. Information is incomplete regarding response of carabid beetles (Coleoptera: Carabidae) to management, and they can serve as indicator species for habitat change caused by disturbance. Therefore, we investigated direct effects of independent and combined applications of repeated, dormant season prescribed burns on a 3-year fire return interval and a one-time application of imazapyr herbicide (Arsenal®) on forest floor carabid assemblages in intensively managed, mid-rotation loblolly pine (Pinus taeda) stands of east-central Mississippi, USA. We captured 1900 individuals dominated by 7 species using pitfall traps from May–October 2004–2007 in a randomized complete block experimental design. Negative responses to treatments by carabid species (i.e., less abundance) were most common, but differential treatment effects by fire with or without imazapyr indicated potential for long-term conservation via increased habitat heterogeneity if mid-rotation treatments are applied across the landscape. [Copyright &y& Elsevier]

Highlights • The effect of MK based materials on the steam cured high performance concrete is investigated. • The XRD and TG analysis were applied to quantify the content of CH and AFt after curing. • The MK based admixtures remarkably refines the ITZ and optimize the pore structure of concrete after heat treatment. Abstract High performance pipe piles are widely used in precast industry. In order to improve the production efficiency and performances of the products, steam curing and mineral admixtures are usually applied. This paper evaluates the performances of HPC pipe piles produced with metakaolin-based admixtures. Quantitative phase composition analysis shows that the addition of 10 wt% metakaolin reduces the portlandite content by up to 57.1%, while increases the content of ettringite to some extent. The addition of metakaolin or metakaolin-slag/limestone blends improves the mechanical properties, especially the hybrid usage of metakaolin and limestone filler. Pore structure and microscope analyze confirm the remarkably-refined pore characteristics caused by the addition of metakaolin-based admixtures, in which case the gel pores accounts up to 85% of the total pores. Those remarkably improved properties caused by the addition of metakaolin-based admixtures indicate a promising future for their applications in producing high performance pipe piles with further modified properties. [ABSTRACT FROM AUTHOR]

The Amur leopard ( Panthera pardus orientalis ) is highly elusive, rare species, critically threatened with extinction worldwide. In this study, we conducted camera-trap surveys of an Amur leopard population in Jilin Province, northeast China. We estimated population abundance and density distribution, and explored the effects of prey population densities and biomass of prey, habitat and anthropogenic factors on the spatial distribution of Amur leopard density. Our results suggested that Amur leopard density was 0.62 individuals/100 km 2 and 16.58 individuals might live within the study area. The spatial distribution of Amur leopard density exhibited different responses to the population densities of different prey species. We found that two ecological thresholds existed in maximum responses of Amur leopard distribution to elevation and prey biomass. Vegetation and anthropogenic factors also showed significant effects on leopard population distribution. In general, there was a combination of habitat factors including, not only prey assembly and biomass, but also vegetation, anthropogenic and geographical factors driving the spatial distribution of Amur leopard population. These insights informed us that comprehensive adaptive landscape and prey conservation strategies should be conducted for saving this critically endangered predator. [ABSTRACT FROM AUTHOR]

• The crystallinity of coal-series and water-washed kaolin are investigated. • The coal-series kaolin with poor crystallinity presents a lower pozzolanic activity. • The increase of amount of AlV and AlVI results in a higher pozzolanic activity. In this paper, we investigated the pozzolanic activity of thermal-activated coal-series kaolin and two types of water-washed kaolin, which were calcined at temperatures ranging from 600 to 700 °C for 3 h. Chapelle test and strength activity index were used to evaluate the pozzolanic activity of thermal-treated kaolin. Results indicated that thermal-activated water-washed kaolin presented a higher pozzolanic activity when calcined at same temperature, which is due to its well-defined morphology, relatively high specific surface area, and high amounts of active aluminum. The incorporation of 10 wt% of calcined kaolin significantly increased the amount of hydrate water and promoted strength development at 7 and 28 days. Moreover, the crystallinity of kaolinite showed obvious impacts on the dehydroxylation temperature and aluminum structure. The optimum dehydroxylation temperature is mainly dependent on the crystallinity of the kaolinite; in addition, the aluminium structure is closely related to the kaolinite crystallinity. Well-crystallized kaolin showed higher pozzolanic activity than poorly crystallized kaolin at the same calcination condition. [ABSTRACT FROM AUTHOR]

• Less than 10% of PG could extend the setting time of AAS pastes. • Multiple tests were conducted to monitor the hydration process. • Ettringite could be generated in AAS samples with more gypsum. • PG made a retardation on the micro development of hardened structure. Effects of phosphogypsum (PG) on hydration process and microstructure of the alkali activated slag (AAS) pastes were discussed in this study, taking the natural gypsum (NG) as a reference. Hydration process was monitored by several kinds of measurements including the isothermal calorimetry, the electrical resistivity, the autogenous shrinkage and the 1H nuclear magnetic resonance. Hydration product assemblages were analyzed by the XRD, NMR, SEM and the mercury intrusion porosimetry (MIP)test. Results showed that less than 10 % of gypsums could retard the setting process of AAS pastes. PG could enhance the late strength although the early strength was decreased, but the addition of NG would reduce the strength at all ages. Induction period and the autogenous shrinkage were both reduced by gypsum gradually. Additionally, PG conducts to the higher MCL and higher polymerization degree of CASH gels than NG. And the addition of PG would refine the pore structure and produce a lower porosity than NG. Furthermore, the comprehensive analysis showed that the setting behavior happened at the initial dissolution period. And PG would delay the acceleration period, indicating the slower development of microstructure. [ABSTRACT FROM AUTHOR]

Cement is the most widely used material and contributes around 8% to the global anthropogenic CO 2 emissions. In 2011 China produced 2.085 Gt cement (60% of the cement production of the world) but the carbon emission from cement industry still not accurately assessed. The LCA (Life Cycle Assessment) method was employed to thoroughly estimate China’s cement industry CO 2 emissions, and results indicated that the carbon emissions of Portland cement clinker, Portland cement, and average cement in China are lower than developed countries. In 2011, the direct CO 2 emission factor and manufactured CO 2 emission factor of China’s average cement manufacture is just 0.4778 t/t and 0.5450 t/t, respectively, and the direct CO 2 emission and manufacture CO 2 emission from China’s cement industry is 0.9983 and 1.1364 Gt, respectively, from the life cycle view, carbon emission of cement industry and the neat carbon emission from cement industry is just 0.8553 and 0.6386 Gt respectively, the share of six carbon emission sources is calculated. The RM CO 2 , FD CO 2 , ED CO 2 , total TD CO 2 and CS CO 2 counts 53.8%, 28.3%, 7.94% and 0.86%, respectively, 29.64% of those carbon emission can be sink by carbonization during 100 years after it cast. The policies to close down outdated facilities and improve recovery the waste heat significantly reduced carbon emission from cement industry, through public, industrial, and technological policies. As the biggest cement producer and consumer in the world, a holistic approach is proposed to slash the carbon emission of cement industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] We hypothesized that diel activities of hamsters have >1 internal oscillators. [•] We hypothesized that diel activities of hamsters are synchronized by weather. [•] Hamsters had three internal oscillators with circadian and ultradian rhythms. [•] Increases in temperature and humidity enhanced the propensity of activity at night. [Copyright &y& Elsevier]

Abstract: Animals in unfamiliar environments may increase exploratory movements, which may result in predation mortalities (the site familiarity hypothesis). Furthermore, increases in resource dispersion may reduce animal foraging time in small patches, and increase movements and home ranges of animals to acquire sufficient resources (the resource dispersion hypothesis). Little is known regarding effects of site familiarity on translocated birds in fragmented landscapes. We translocated 130 eastern wild turkeys (Meleagris gallapovo silvestris) in a sex ratio of one male to 4 females to 2 study sites that differed in forest fragmentation in MS, USA. Turkeys were captured from sites throughout Mississippi during springs 2009 and 2010. We monitored movements of translocated wild turkeys using radio telemetry. Movement distances and home ranges in 2010 did not differ among birds released in different years, inconsistent with the site familiarity hypothesis. However, movement distances and home ranges of translocated turkeys were greater at the more fragmented site than at the less fragmented site, supporting the resource dispersion hypothesis. Moreover, home range sizes were related positively to within-home-range variability in vegetative greenness measured by the normalized difference vegetation index. Effects of resource dispersion may override effects of site familiarity concerning translocated wild turkeys. [Copyright &y& Elsevier]

Abstract: Mating system and philopatry influence the genetic structure of a social group in mammals. Brandt''s vole (Lasiopodomys brandtii) lives in social groups year-round and has male biased dispersal, which makes the vole a model system for studies of genetic consequences of mating system and philopatry. This study aimed to test the hypotheses that: (1) multiple paternity (MP) would exist in Brandt's voles, enhance offspring genetic diversity and reduce genetic relatedness between littermates; (2) promiscuity would occur in this species in that males and females mate with multiple partners; and (3) plural breeders of a social group would be genetically related because of philopatry of female juveniles in Brandt''s voles. Paternity analysis indicated that MP occurred in 11 (46%) of 24 social groups examined and that promiscuity existed in this species. Multiple paternity litters had twice the offspring genetic diversity and half the average within-litter genetic relatedness of single paternity litters. We also found plural breeding females in six social groups. Average pairwise genetic relatedness of plural breeders ranged from 0.41 to 0.72 in four social groups, suggesting first-order kinship. Future studies need to investigate effects of reproductive skew and MP on population genetic structure of Brandt''s voles. [Copyright &y& Elsevier]