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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.

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.

There is no temperature stress and temperature curling according to the present cement concrete pavement design, when the temperature gradient of cement concrete pavement in service is zero, and it does not consider the effect of Built-in curling caused in early-age setting process of cement concrete to cement concrete pavement in service. In fact, there is Built-in curling in cement concrete slab when it is after the completion of the cement concrete slab is poured, and the curling is mainly upward. It is in the setting process, when cement concrete is on the final set, the cement concrete is at the critical moment when is just able to bear load, and it exists temperature gradient but no strain in the pavement slab, the temperature gradient is known as "Built-in construction temperature gradient" in AASHTO2002 design guidance, and it is the important part of the Built-in curling. In this paper, cement concrete beam specimens were poured in outdoor and temperature sensor and strain sensor were buried in the cement concrete specimens to detect early-age internal temperature field and strain field, and then the study of Built-in curling and Built-in construction temperature gradient were carried out.

A simple and rapid green synthesis using Bischofia javanica Blume leaves as reducing agent was developed for the preparation of gold nanoparticles (AuNPs). AuNPs decorated graphene oxide (AuNPs/GO) was prepared and employed for the sensitive amperometric determination of chloramphenicol. The green biosynthesis requires less than 40s to reduce gold salts to AuNPs. The formations of AuNPs and AuNPs/GO were evaluated by scanning electron and atomic force microscopies, UV-Visible and energy dispersive X-ray spectroscopies, X-ray diffraction studies, and electrochemical methods. AuNPs/GO composite film modified electrode was fabricated and shown excellent electrocatalytic ability towards chloramphenicol. Under optimal conditions, the amperometric sensing platform has delivered wide linear range of 1.5-2.95μM, low detection limit of 0.25μM and high sensitivity of 3.81μAμM(-1)cm(-2). The developed sensor exhibited good repeatability and reproducibility, anti-interference ability and long-term storage stability. Practical feasibility of the sensor has been demonstrated in food samples (milk, powdered milk and honey) and pharmaceutical sample (eye drops). The green synthesized AuNPs/GO composite has great potential for analysis of food samples in food safety measures.

This article examines an integrative vision of the relationship between nature and the city appearing in a late nineteenth-century American weekly magazine entitled Garden and Forest (1888–...

Rapid determination of the properties of lignocellulosic material is highly desirable for biomass production and utilization. In the present study, measurements of woody biomass digestibility and chemical composition using near-infrared reflectance (NIR) spectroscopy were calibrated. Poplar and eucalyptus materials were recorded in NIR spectrum as well as determined for their chemical compositions of Klason lignin, α-cellulose, holocellulose, lignin syringyl/guaiacyl (S/G) ratio and enzymatic digestibility. Fitting of the NIR information with chemical properties and digestibility by partial least-squares (PLS) regression generated a group of trained NIR models that were able to be used for rapid biomass measurement. Applying the models for woody biomass measurements led to a reliable evaluation of the chemical composition and digestibility, suggesting the feasibility of using NIR spectroscopy in the rapid characterization of biomass properties.

Based on new census surveys recently performed by local government representatives, as well as two complementary and expanded expeditions conducted in 1997 and 2004, we present an updated database of the distribution of known native Metasequoia glyptostroboides trees in an area formed by western Hubei, eastern Chongqing, and northern Hunan in south-central China. The area is located between longitudes 108°20′E (Huangshui Town, Shizhu County, Chongqing) and 109°40′E (Tani Township, Longshan County, Hunan) and 30°10′N (Jiannan Town and Moudao Town, Lichun City, Hubei) and latitudes 29°10′N (Luota Township, Longshan County, Hunan). A total of 5396 native Metasequoia trees exist either as scattered (isolated) individual trees or in populations from two regions of this area. The majority of trees (5391 trees) grow in the first region, which includes eastern Chongqing and western Hubei. Only five trees exist in the second region at western Hunan. The database provides an updated census for the current ...

Rutting is one of the major distresses of highway pavements in China. Presently, rut depth is the only evaluation index for rutting in China and abroad. However, rut depth can't show the entire extent of rutting. In this research, a rut-meter is developed independently, which is used for inspecting rut of several expressway pavements. The results show that the shapes of rut were different, and the shape of rut affects traffic safety. Multi-indexes are adopted, such as rut depth, rut width, maximum possible water catching area, and average rut curvature radius, in order to describe the characteristics of rut and the relation between rut and traffic safety. The study lays a foundation for more rational new rut indexes.

Masked o-benzoquinones generated in situ from o-methoxyphenols and methanol undergo Diels—Alder reaction with 1-vinylcyclohexenes to provide decahydrophenanthrenes along with bicyclo[2.2.2]octenone derivatives.

An adaptive multiuser decision-feedback equalizer (DFE) companioned with a Kalman channel estimation algorithm is presented for DS-CDMA systems in multipath fading channels. The Kalman channel estimation algorithm is employed to estimate the multipath fading channels, then the estimates are used to adjust the tap coefficients of the multiuser DFE via a minimum mean-square error design criterion. In this study, we present a novel state-space equation, which is different from the joint multiuser detection/channel estimation method (Wang and Poor, Wireless Networks 4(6) (1998) 453–470), for the multipath fading channel estimation of multiuser DS-CDMA systems. We take not only the estimates of channels but also the statistics of the channel estimation errors into consideration of the multiuser DFE design. We also derive the output signal-to-interference-and-noise ratio and the bit-error-rate for the multiuser detection, in which the influence of multiuser interference, channel estimation errors and channel noise is included. Finally, two fading channel models, i.e., the land-mobile model and the Butterworth model, are simulated to demonstrate our results. The sensitivity of the proposed method to the uncertainties of fading channel parameters is also presented in the simulations.

Factoring plays a crucial role in solving the financing problems, which are common among small and medium enterprises (SMEs). In this paper, we develop decision models by considering non-recourse factoring and recourse factoring respectively in a supply chain which includes a bank and a seller. Then we find the optimal discount rate of factoring in two scenarios. Finally, we study the influence of the seller's equity fund and the probability of bad debts on the discount rate of factoring by numerical example and sensitivity analysis.

This study was carried out in five full-term newborn babies and 11 patients with anorectal anomalies (five of whom had high deformity, five had intermediate, and one had low), using the modified Bielschowsky method. The following four kinds of sensory nerve ending were found: muscle spindle in the puborectalis and the external anal sphincter, Pacinian corpuscle in the plane between the internal anal sphincter and the external anal sphincter and in the presacral space, globular ending in the presacral space, and free nerve ending in the epithelium of the anal canal and in the perianal skin. It was found that there were significantly fewer muscle spindles in the puborectalis and many fewer Pacinian corpuscles and globular endings in the presacral space of high and intermediate deformities than normal. No spindle was found in the external sphincteric muscles of the deformities. On the other hand, the Pacinian corpuscles and the globular endings of high and intermediate deformities lagged behind normal in development. The densities of the nerve bundles in the subepidermis and the nerve fibers in the dermis of perineal region in high and intermediate deformities were much lower than normal, and the decrease in density corresponded to the levels of the rectal pouch. The observation showed that the agenesis of sensory nerve endings in the puborectalis and the anal region was one of the most significant pathological features in high and intermediate types of anorectal anomalies, and might be responsible for the abnormalities of the reflex of the anal sphincter and the anal sensation in such patients. The muscle spindles in the puborectalis may be only potential receptors for the reflex and sensation after surgery.

Steel coating technology has made great progress in recent years to meet the demand for corrosion-resistant steel. Fe-Zn coated steel sheet is one of those which has been developed with increasing production in response to the brisk demand in the automobile, construction and household electrical appliance industriesThe adhesion of coating to substrate is a critical property of any coating system for mechanical integrity and environmental protection of the substrate. The investigation of fracture on the coating layer and/or on any interfaces after deformation, specially the initiation of failure provides fundamental acknowledge to understand major factors contributing to the adhesion of coatings. This paper presents the results of fracture on Fe-Zn alloy coatings on steel sheets after deformation.