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This article traces the environmental history of the first fifty years of the Tsingtao Brewery, investigating how a popular mass-produced commodity transformed a local landscape, industrial...

As a common human behavior, interaction is everywhere in human life. With the rise of big data and human–computer interaction in the 21st century, more and more researchers from different industries and disciplines pay great attention to the human interactive behavior research. From the perspective of computer science, scholars try to use computer technology to make research more meaningful. To the best of our knowledge, this paper is the first study to investigate the potential rules of human interactive behavior in the view of computer science, based on 16 top-tier journals of human interactive behavior from Microsoft Academic Graph dataset. We put forward a topic extraction and clustering model based on word2vec to infer key topics, which can be widely used in different fields of research. We find that the growth of human interactive behavior is in an uptrend on the whole. Besides, the cooperative relationship between authors and countries/regions is closer over time. We also make the mensurable evolution analysis of topics by a statistical method. Some topics are hot all the time, while some are unpopular as time goes by. Finally, we do rankings in the field of human behavior research from a new perspective. All these findings help researchers observe potential patterns and the topic evolution in half a century, which may shed dazzling light on the exploration of human interactive behavior.

A collective reinglesflection on doing environmental history in pandemic times

In order to study the effect of B-position element substitution on strontium doped lanthanum manganate microstructure and resistivity temperature property, the cobalt substituted strontium doped lanthanum manganate ceramic powders with La0.6Sr0.4CoxMn1-xO3 as the main component was prepared by sol gel method combined with heat treatment process at first, then the cobalt substituted strontium doped lanthanum manganate films was prepared by silk-screen printing on the Alumina ceramic substrate. The results showed that when the x value sequentially varied from 0 to 0.2,0.4,0.6,0.8, the particle size property of films would be changed by the change of the crystal structure, which was produced by the B-position cobalt substitution. It could be seen from the results that the average radius of the five powders were concentrated in the range of 16.4-19.6nm.

The characterization results of hollow ceramic beads show that oxidant KClO3 had a great influence on the preparation of hollow ceramic beads. The morphology picture and XRD analysis showed that the surface of hollow beads without KClO3 was smooth, and the particle size analysis results show that the particle size was 10 ~ 50μm. Without KClO3, the average particle size is 28.08 μm; After adding KClO3, dense dendritic crystal structure was distributed on the surface of hollow beads, and the phase is mainly BaFe2O4, and the distribution range of hollow beads is 5 ~ 40 μm, and the average particle size is 16.02 μm° It could be inferred from the analysis that the quenching reaction is fully carried out after the addition of KClO3, resulting in a large amount of gas, reducing the volume of ceramic droplets and reducing the particle size of hollow beads.

When ferrite hollow beads were made into coating materials, because ferrite hollow beads had hollow internal structure and conductive and magnetic ball wall, ferrite hollow beads have typical resonant ball characteristics in structure. The absorbing coating composed of numerous ferrite hollow beads could be considered as a resonant absorber. With the rapid development of information technology, especially computer technology, the introduction of computer simulation technology can often save experimental costs and reduce the blindness of experiments. Therefore, in order to comply with this development trend, this chapter will establish the absorber model of ferrite hollow bead coating based on HFSS (high frequency simulator structure) electromagnetic simulation software, and qualitatively analyze the relationship between the thickness of ferrite hollow bead coating and the resonant frequency of absorber and the distribution state of electromagnetic field inside the coating through the of computer simulation software.

Unraveling the mechanisms causing restricted regeneration and limited distribution range has become a core issue for biodiversity conservation. Anthropogenic disturbances are changing a variety of ecological factors, but how their relative importance varies across multiple regeneration stages is still unclear even in a single species. In this study, we focused on Metasequoia glyptostroboides, a relict species suffering a severely restricted regeneration in the wild, and performed controlled experiments using 54,600 seeds to investigate seedling emergence and growth in both its natural and adjacent unoccupied habitats to disentangle the roles of seed availability, interspecific competition and herbivore/omnivore attack across early regeneration stages. Our results showed that these factors mainly exerted their predominant effects at initial regeneration stages. Compared with herbivore/omnivore attack, seed availability and interspecific competition were the crucial factors regulating seedling emergence. The first-year seedling survival rate was only significantly influenced by interspecific competition, and the survival of second-year seedlings was independent of all these factors. Moreover, we detected similar impacts of these factors in the adjacent unoccupied habitats to those in the natural habitats, indicating their roles in limiting population expansion. Our findings provide some suggestions to assist the natural regeneration and range expansion of M. glyptostroboides, and our experiment design can be applied in the assessment of endangerment causes for other endangered plants.

Herein, we report the preparation of nanorods-like Cd(OH)2-rGO nanocomposites via using a simple co-precipitation method. The as-prepared Cd(OH)2-rGO materials were characterized by a variety of analytical and spectroscopy techniques such as scanning electron microscope (SEM), elemental analysis (EDX), X-ray diffraction (XRD), and Raman spectroscopy. Interestingly, Cd(OH)2-rGO modified glassy carbon electrode (GCE) employed for the electrochemical detection of acetaminophen (AP) sensor for first time by using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The AP sensor exhibited an ultra-high sensitivity of 24.452 µA µM−1 cm−2 and a low detection limit 0.08 µM with wider linear ranges from 0.1 to 102 µM. Notably, the obtained analytical parameters of the AP sensor using nanorods-like Cd(OH)2-rGO modified GCE is superior than several rGO based nanocomposites suggesting more suitable for several practical pharmaceutical applications.

In the present investigation, we report a facile, reproducible and effortless biological synthesis of silver nanoparticles (Ag-NPs) utilizing Cerasus serrulata (C. serrulata) leaves extract as reducing as well as stabilizing agent. The size of synthesized Ag-NPs was in the range of 15–24 nm when examined with transmission electron microscopy (TEM) and X-ray diffraction studies. The Ag-NPs obtained using C. serrulata exhibited excellent catalytic activity towards reduction of 4-nitrophenol (4-NPh) to 4-aminophenol in the presence of NaBH4 and demonstrate noteworthy electrochemical performance for 4-NPh reduction. The linear range, detection limit and sensitivity are estimated as 0.09–82.5 μM (r = 0.991), 0.06 μM and 3.0 μA μM−1 cm2 respectively. The Ag-NPs were found to show higher antimicrobial efficiency against Streptococcus mutans and Staphylococcus aureus.

ZnO nanorods have been successfully grown on Ga doped (0–5 wt%) ZnO seed layer by using simple hydrothermal method. Changing Ga content in the seed layers lead to formation of ZnO nanorods with high aspect ratio and increased density. The effects of Ga doped seed layer on optical and structural morphology of ZnO nanorods are investigated in detail by using Field-emission scanning electron microscope (FESEM), X-ray diffraction (XRD) and Photo luminescence spectroscopy (PL). It has been observed that the Ga doped seed layer strongly affected the structural morphology of ZnO nanorods. XRD results show that all the samples have hexagonal wurtzite shape and (0 0 2) is preferred direction of growth. The intensity of (0 0 2) peak increases with increasing Ga concentration in seed layer indicating that the Ga doped seed layer has promoted growth of nanorods along (0 0 2). SEM images show a decrease in diameter of ZnO nanorods with increasing Ga concentration in seed layer. The PL spectra of all the samples have two emission bands, UV and defect emission. UV emission shows a small blue shift with increasing Ga concentration in seed layer. The photocatalytic activity of as grown ZnO nanorods increases with aspect ratio (length) and density.

Fe+MnO +Fe2O3+ZnO reaction system was used to prepare Mn-Zn ferrite flake absorbent by self-reactive spray forming technology. Extrinsic enthalpy (H) and adiabatic temperature (Tad) of system were calculated. The formation mechanism and electromagnetic properties of Mn-Zn ferrite flake absorbent were analyzed. The results show that Tad exceeded 1998K, self-propagation reaction can be ignited and products can be melted. The droplets impacted onto copperplate to achieve flake shape. SEM and XRD were used to characterize the morphology and phase of samples. The results show that most of flake absorbent are at 100μm wide and 10μm thick, and they are constituted by pure Mn0.5Zn0.5Fe2O4 phase with spinel crystal structure. Absorption test show that the absorbent has two absorption peaks, the minimum value of reflectivity is at -27dB and the bandwidth lower than -10dB reaches to 3.5GHz. The Mn-Zn ferrite flake absorbent provides with preferable properties, which is potential in the further investigations.

Masked o-benzoquinones (MOBs), which were generated in situ from 2-methoxyphenols, underwent Diels–Alder reactions with 1-vinylcyclohexenes to produce the corresponding cycloaddition products, that is, decahydrophenanthrenes along with bicyclo[2.2.2]octenones. In the former case, the MOBs serve as the dienophile, and in the later case, the 1-vinylcyclohexenes act as the dienophile. The obtained bicyclo[2.2.2]octenones could be transformed into the corresponding decahydrophenanthrenes through a Cope rearrangement at 220 °C. Thus, these tandem reactions provide a short and efficient entry to the decahydrophenanthrene skeleton from easily available 2-methoxyphenols.

Adopting self-reaction quenching technology based on flame spraying technique, self-propagating high-temperature synthesis and quick chilling technique, hollow multiphase ceramic microspheres are prepared. With Al+Cr2O3+Fe+Fe2O3+MnO2 as reactive system, agglomerate powders are obtained and then distinguished as thick powders and fine powders according to the different particle size. The relationship between agglomerate powders initial particle size and hollow ceramic microspheres is analyzed by the means of SEM, EDS, XRD and particle-size analyzer. The result shows that average particle diameter of thick powder is 24.49μm and that of fine powder is 17.15μm. Particle diameters of thick powder quenching product distribute within the range of 20~50μm, and those of fine powder distribute within the range of 5~30μm. The thick powder quenching product phase composition consists of Mn2AlO4,Fe2O3,Fe3O4,FeCr2O4,Cr2O3,Al2O3The fine powder quenching product phase composition consists of Mn2AlO4,Fe2O3,FeCr2O4,Fe3O4.