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This study combines several approaches to investigate bronze objects uncovered at the Thengkham East site in Vilabouly in 2018. According to SEM-EDS research, most copper wares are binary alloys of copper and tin. Metallography (OM) studies have demonstrated that generally, the forming technique of copper wares is casting, and the microstructure of extensive annealing is shown in some areas of isolated weapons. The experimental results for this set of samples were consistent with the previously published style of Vilabouly copperware. Comparative investigations suggest that multiple sites within Vilabouly had similar metallurgical industry technology and that there is a possibility of exchanging intermediate goods between mining/ore processing sites and ordinary consuming locations. Lead isotope studies have corroborated the prevailing opinion that during the early Iron Age in Ban Non Wat, central Laos superseded Thailand in supplying copper to various sections of the Indo-China Peninsula. Given Lead isotope analysis also indicate that there had been connections between Thailand, Laos, and Cambodia in the metallurgical industry during the same period, this study provides support for the hypothesis that incorporate northeastern Cambodia into the medium-range interaction zone where central Laos is located.

In recent years, the automatic extraction of remote-sensing image information has attracted full attention. However, the particularity of remote-sensing images and the scarcity of data sets with label information have brought new challenges to existing methods. Therefore, we develop a lightweight semantic segmentation network based onmultiscale feature fusion (MFF) and attention refinement (MFFANet). Our network relies on three crucial modules for improved performance. The multiscale attention refinement module strengthens the representation ability of feature maps extracted by the deep residual network. The MFF module aggregates the information carried by the high-level and low-level features while restoring the image resolution. Furthermore, the boundary enhancement module captures boundary details to solve the semantic ambiguity problem. We achieve 83.5% mean intersection over union (MIoU) on the Urban Semantic 3-D (US3D) data set and 69.3% MIoU on the Vaihingen data set with only 8.2M parameters.

In this paper, the unified Jacobi–Ritz method (JRM) is utilized to analyze the dynamic response of rectangular plates with general boundary conditions. First, the structural energy functional is established in the framework of the first-order shear deformation theory, and the rectangular plate is divided into several equal parts according to the domain decomposition method. Then, the artificial springs are introduced to ensure the continuity of segments and diversified boundary conditions. The Jacobi orthogonal polynomials are expanded to represent the displacement field in one direction. Finally, the free and forced vibration characteristics of the rectangular plate can be obtained by utilizing the Rayleigh–Ritz method, where the Newmark-β integration method is adopted to realize the time-domain solutions for transient vibration response. The results for different structural scale parameters and various boundary conditions are presented, and the validity and accuracy of the presented method are verified by comparing the results from published literature and FEM. The results of the study can provide technical support for vibration control of the plate structure.

For the plate or multicabin structure of ships, the vibration transmission characteristics have a great correlation with the structural mode. When the excitation force frequency get close to the natural frequency of the structure, strong vibration and sound radiation will occur. Therefore, it is very important and meaningful to study the vibration characteristics and protection methods of ship structures. Based on the classic finite element method, this article studies the influence of structural forms and parameters on the vibration characteristics of typical ship structures. Taking the multicabin structure as a benchmark structure model, the influence of the structural form on vibration mode and transmission characteristics of the target deck and other cabin decks in the multicabin structure was analyzed. Then, without changing the original structural layout, the effects of different structural parameters on the vibration mode and transmission characteristics were analyzed. Finally, the vibration protection process of the ship structure was formed. The results of this study can provide methodological basis and data reference for relevant research in future.

At present, in addition to the high-strength alloy steel still used in the main load-bearing structure of foreign nuclear submarines, many composite materials have been used for non-load-bearing components, and the common laminate is the main form of the composite plate and shell. The composite laminate with a carbon/glass hybrid material has excellent structural mechanical properties. The vibration and acoustic radiation theories of the composite laminate were analytically deduced, the effect of ply parameters in hybrid shell plates was analyzed, and the influence of the hybrid ratio on the stiffness of shell plate was also investigated. Furthermore, according to the theoretical description, the typical carbon/glass hybrid shell plate was designed and the experimental comparison on the vibro-acoustic properties with a steel plate was carried out. The results showed that the mass and stiffness of a 12 mm carbon/glass hybrid shell plate were only 30 and 70% compared with an 8 mm steel plate. The mass and stiffness of a 15 mm carbon/glass hybrid shell plate were about 40 and 160% of that of an 8 mm steel plate, and its vibration and noise reduction performance was far superior to the steel plate. Therefore, the composite shell plate can achieve excellent acoustic performance while meeting the structural-functional indicators.

Background: We evaluated the association between higher resting heart rates (RHRs) and adverse events in COVID-19 patients. Methods: One hundred and thirty-six patients with laboratory-confirmed COVID-19 were admitted. Outcomes of patients with different RHRs were compared. Results: Twenty-nine patients had RHRs of 2) and higher temperatures, and there was a higher proportion of men upon admission (all P < 0.05). Patients with higher RHRs showed higher white blood cell counts and D-dimer, cardiac troponin I (TnI), N-terminal pro-B-type natriuretic peptide and hypersensitive C-reactive protein levels, but lower albumin levels (all P < 0.05) after admission. During follow-up, 26 patients died (mortality rate, 19.1%). The mortality rate was significantly higher among patients with tachycardia than among the moderate and low RHR groups (all P < 0.001). Kaplan–Meier survival curves showed that the risks of death and ventilation use increased for patients with tachycardia (P < 0.001). Elevated RHR as a continuous variable and a mean RHR as tachycardia were independent risk factors for mortality and ventilator use (all P < 0.05) in the multivariable adjusted Cox proportional hazards regression model. Conclusions: Elevated average RHRs during the first 3 days of hospitalisation were associated with adverse outcomes in COVID-19 patients. Average RHRs as tachycardia can independently predict all-cause mortality.

Deep eutectic solvent (DES) is a kind of green solvent for biorefinery, which favors the progress of being more environmentally friendly and effective. A better understanding of structural changes of lignin is necessary to optimize pretreatment conditions and efficient utilization of the resultant lignin. The current study reported the structural features of lignin recovered from alkaline ChCl/imidazole and ChCl/urea DES pretreatment, and the mechanism of lignin modification was revealed. The profiling demonstrated that lignin samples possessed a high purity (>94.4%), low molecular weight ranging from 1544 to 2562 g/mol and an excellent uniformity (PDI < 1.6). Noteworthy, the content of β-O-4' linkages in lignin was over 75% (i.e. 72.2%-77.4% retention); S/G ratio was increased whereas the content of -OCH3 groups were decreased. It was revealed that slight cleavage of β-O-4' linkages, preferential breakdown of G units, and demethylation reaction were occurred during alkaline ChCl-based DES pretreatment. Specifically, cleavage of ester linkages between PB and lignin macromolecule was taking place during ChCl/imidazole pretreatment at a high temperature; whereas oxidation only appeared in ChCl/urea system. Despite the modification, well β-O-4' preserved and less condensed lignin samples were recovered after low-temperature pretreatment. Consequently, high contents of phenol derivatives (26.3-30.6%) were achieved in lignin oil. The present study provides critical information on alkaline ChCl-based DES pretreatment, which will contribute to the valorization of lignin by-products and will be beneficial to the development of biorefineries.

Desertification leads to the extreme fragility of ecosystems and seriously threatens ecosystem functioning in desert areas. The planting of xerophytes, especially leguminous shrubs, is an effective and common means to reverse desertification. Soil microorganisms play a crucial role in nutrient cycling and energy flow in ecosystems. However, the effects of introducing leguminous shrubs on soil microbial diversity and the relevant mechanisms are not clear. Here, we employed the high-throughput absolute quantification 16S rRNA sequencing method to analyze the diversity of soil bacteria in sand-fixing areas of mixed shrublands with three combinations of shrubs, i.e., C. korshinskii × Corethrodendron scoparium (CaKCoS), C. korshinskii × Calligonum mongolicum (CaKCaM), and C. scoparium × C. mongolicum (CoSCaM), in the south of the Mu Us Sandy Land, China. This area suffered from moving dunes 20 years ago, but after introducing these shrubs to fix the dunes, the ecosystem was restored. Additionally, the effects of soil physicochemical properties on soil bacterial composition and diversity were analyzed with redundancy analysis (RDA) and structural equation modeling (SEM). It was found that the Shannon index of soil bacteria in CaKCoS was significantly higher than that in CaKCaM and CoSCaM, and the abundance of the dominant phyla, including Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Planctomycetes, Thaumarchaeota, Armatimonadetes, candidate_division_WPS-1, and Nitrospirae, increased significantly in CaKCoS and CaKCaM compared to that in CoSCaM. RDA showed that the majority of soil properties, such as total nitrogen (TN), available potassium (AK), N:P ratio, soil moisture (SM), and available phosphorus (AP), were important soil environmental factors affecting the abundance of the dominant phyla, and RDA1 and RDA2 accounted for 56.66% and 2.35% of the total variation, respectively. SEM showed that the soil bacterial α-diversity was positively affected by the soil organic carbon (SOC), N:P ratio, and total phosphorus (TP). Moreover, CaKCoS had higher SM, total carbon (TC), total potassium (TK), and AP than CaKCaM and CoSCaM. Collectively, these results highlight a conceptual framework in which the combination of leguminous shrubs can effectively drive soil bacterial diversity by improving soil physicochemical properties and maintaining ecosystem functioning during desertification reversal. Graphical Abstract

Accurate detection and segmentation of obstacles is the key to the smooth operation of the planetary rovers and the basic guarantee of scientific exploration mission. The traditional method of rock...

Microbial enzymes are crucial for material biotransformation during the composting process. In this study, we investigated the effects of adding bamboo charcoal (BC) (i.e., at 5%, 10%, and 20% corresponding to BC5, BC10, and BC20, respectively) on the enzyme activity levels during chicken manure composting. The results showed that BC10 could increase the cellulose and urease activities by 56% and 96%, respectively. The bacterial community structure in BC10 differed from those in the other treatments, and Luteivirga, Lactobacillus, Paenalcaligenes, Ulvibacter, Bacillus, Facklamia, Pelagibacterium, Sporosarcina, Cellvibrio, and Corynebacterium had the most important roles in composting. Compared with other treatments, BC10 significantly enhanced the average rates of degradation of carbohydrates (D-xylose (40%) and α-D-lactose (44%)) and amino acids (L-arginine (16%), L-asparagine (14%), and L-threonine (52%)). We also explored the associations among the bacterial community and their metabolic functions with the changes in the activities of enzymes. Network analysis demonstrated that BC10 altered the co-occurrence patterns of the bacterial communities, where Ulvibacter and class Bacilli were the keystone bacterial taxa with high capacities for degrading carbon source, and they were related to increases in the activities of cellulase and urease, respectively. The results obtained in this study may help to further enhance the efficiency of composting.

Background and Objectives The pandemic of coronavirus disease 2019 (COVID-19) remains to be the biggest public threat all over the world. Because of the rapid deterioration in some patients, markers that could predict poor clinical outcomes are urgently required. This study was to evaluate the predictive values of cardiac injury parameters, including cardiac troponin I (cTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, on mortality in COVID-19 patients. Methods COVID-19 patients in Zhongfaxincheng branch of Tongji Hospital (Wuhan, China) from February 8–28, 2020, were enrolled in this study. We followed up the patients for 30 days after admission. Results A total of 134 patients were included in the study. Multivariate Cox regression showed that 1) patients with elevated cTnI levels had a higher risk of death (hazard ratio [HR] 7.33, 95% confidence interval [CI] 2.56–21.00) than patients with normal cTnI levels; 2) patients with elevated NT-proBNP levels had a higher risk of death (HR 27.88, 95% CI 3.55–218.78) than patients with normal NT-proBNP levels; 3) patients with both elevated cTnI and NT-proBNP levels had a significantly higher risk of death (HR 53.87, 95% CI 6.31–459.91, P < 0.001) compared to patients without elevated cTnI or NT-proBNP levels; 4) the progressions of cTnI and NT-proBNP levels were also correlated with death (HR 12.70, 95% CI 3.94–40.88, P < 0.001 and HR 51.09, 95% CI 5.82–448.26, P < 0.001). Conclusions In COVID-19 patients, cTnI and NT-proBNP levels could be monitored to identify patients at a high risk of death in their later course of disease.

Composite materials have become a research hotspot in the field of vibration and noise reduction for their high strength, high damping, and other outstanding mechanical properties in recent years. In this paper, the effect of laminated materials on the dynamic performance of floating rafts is investigated based on modal superposition theory using the finite element method. The detailed derivation of the modal superposition theory was made, and taking T700 fiber-reinforced composite material as an example the damping effect of the floating raft structure in three cases was discussed: whether the composite material is laid or not, different layup angles, and different layup positions. The research shows that laying composite materials can improve damping effect of the floating raft and the changes in both the laying angle and the laying position will affect its dynamic performance. Moreover, the damping performance of the structure is inversely correlated with its stiffness within a certain range.

Because of their extremely broad spectrum and strong biocidal power, nanoparticles of metals, especially silver (AgNPs), have been widely applied as effective antimicrobial agents against bacteria, fungi, and so on. However, the mutagenic effects of AgNPs and resistance mechanisms of target cells remain controversial. In this study, we discover that AgNPs do not speed up resistance mutation generation by accelerating genome-wide mutation rate of the target bacterium Escherichia coli. AgNPs-treated bacteria also show decreased expression in quorum sensing (QS), one of the major mechanisms leading to population-level drug resistance in microbes. Nonetheless, these nanomaterials are not immune to resistance development by bacteria. Gene expression analysis, experimental evolution in response to sublethal or bactericidal AgNPs treatments, and gene editing reveal that bacteria acquire resistance mainly through two-component regulatory systems, especially those involved in metal detoxification, osmoregulation, and energy metabolism. Although these findings imply low mutagenic risks of nanomaterial-based antimicrobial agents, they also highlight the capacity for bacteria to evolve resistance.

The transient impact load during the launch of a rocket at sea threatens the safety of the launcher and the deck structure of the launch platform. In view of the impact resistance of the offshore rocket launcher system, this paper takes the real-scale rocket launcher system as the research object and establishes the analysis model of the fiber-reinforced composite rocket launcher based on the finite element method. Then, we explore the factors of the thickness by finite element simulation method and the angle and the position of IM7 fiber-reinforced composite, which influence the impact resistance property of the rocket launcher. The results show that the fiber-reinforced composite rocket launcher can effectively reduce the impact response of the structure and improve the impact resistance of the structure. The best laying scheme is to lay four layers of IM7 fiber material on both sides of the panels of the fixed bracket and the webs of the erector, respectively, with a single layer thickness of 0.75 mm and a laying angle of [90°/∓45°/90°].

The uniform formulation of dynamic vibration analysis of multispan beams is presented by using an efficient domain decomposition method in this paper. Firstly, the structure is divided into several equal sections based on domain decomposition method. Next, the artificial spring is used to simulate complex boundaries and continuity condition of multispan beam. Finally, the admissible displacement functions are expanded through Jacobi orthogonal polynomials, and the free and forced vibration characteristics of multispan beam structures can be obtained by using Rayleigh–Ritz method. Results for various boundary conditions, ratios of thickness to length (h/L), numbers, and stiffness of supporting springs are presented. It is clearly shown that accurate solutions can be obtained by using the proposed method, and this study extends the application range of the Jacobi polynomials-Ritz method. In addition, the research results of this paper can provide data support for engineers such as bridge designers to design multispan bridges.

Nano-ZnO were in situ prepared and permanently embedded in regenerated cellulose (RC) films by chemical precipitation to endow antibacterial of films and simultaneously strengthen tensile strength. ZnCl2 was selected as a promoter of 1-allyl-3-methylimidazolium chloride for cellulose dissolution and as a precursor for nano-ZnO synthesis. Zn2+-absorbed cellulose solution was reacted with NaOH under ultrasonic to obtain nano-ZnO embedded RC films. The results indicated that RC films treated with the longest sonication time, highest regeneration solution basicity, and highest cellulose concentration were demonstrated to be the most effective against S. aureus, which agreed well with the dense and homogeneous distribution of high content of nano-ZnO on the film surface. The nanocomposite films achieved particularly high mechanical strength of 202.0 MPa with improved thermal stability. Strong H-bonding formed between nano-ZnO and cellulose, which contributed to high tensile strength and thermal stability of films. This work affords a simple approach to prepare cellulose nanocomposite with outstanding performance for potential application in packaging.

Pore ice content is crucial in evaluating the mechanical properties of frozen soils. Existing strength criterion models are usually empirical and ignore the influence of pore ice content. By assuming that the critical state shear stress ratio of soil is a function of the stress level, a critical state line of frozen soil is proposed to consider pore ice content. By combining the Mohr-Coulomb (M-C) and Drucker-Prager strength criteria to describe the failure shape characteristics on the deviatoric plane, a new strength criterion is established for complex stress conditions. The proposed model is validated against existing models and measured data in the literature. In addition, the proposed model can uniformly describe the CSL of different types of geotechnical materials and has a clear physical meaning, which may provide a theoretical basis for constitutive models.

It is crucial for energy storage devices to manufacture the thick electrode with high energy and power density. The electrochemical performance of the commercial porous carbon supercapacitor electrode fabricated by traditional methods is highly dependent on the electrode thickness. Therefore, a cost-effective method is required to fabricate thick electrode with high mass loading, high specific capacitance and superior rate performance. Herein an ultra-thick cubic electrode is fabricated based on lignin carbon aerogel/nickel (LCAN) bulk with binary network structure using polymerization under ZnCl2 hypersaline condition. This is an efficient and low-cost route to prepare carbon aerogels without drying under rigorous condition and ZnCl2 is an ideal porogen, activating agent and hard template for LCAN. The precise adjustment of ZnCl2/lignin ratio and the combination of LCAN binary network results in the cubic electrode (thickness up to 4.2 mm), with an ultra-high areal capacitance of 26.6 F cm−2 (63% retained from 1 to 200 mA cm−2), an excellent cycle stability even with high mass loading (∼147 mg cm−2) and myriad shapes. These features represent the highest areal capacitance values reported carbonaceous thick electrodes. With these unique features, this study represents a promising 3D thick electrodes for energy-related devices.

The progress on human pose estimation by deep neural networks has been significantly advanced in recent years. However, the problem of precision loss caused by the prediction of the coordinates back to the original image has been neglected. In this paper, we propose a simple but effective method using Heatmap and Offset for Pose Estimation (HOPE). In order to solve the human pose estimation problem, firstly a general top-down method is used in HOPE to generate the human detection box based on a detector, and then the keypoints in each cropped box image are located. To alleviate the precision loss of mapping process, HOPE embeds the coordinate offset into the structure of the neural network, allowing the network to self-learn the slight offset in the mapping process in an end-to-end manner, which improves the accuracy in the current field of pose estimation. Experimental results on the multi-person pose estimation dataset MSCOCO, the single-person pose estimation dataset MPII and CrowdPose Pose Estimation dataset indicate that our method achieves state-of-the-art performance in terms of accuracy and computational complexity.

The Sinan shipwreck, discovered in the waters of Sinan gun, Jeollanam-do, South Korea, sank in June 1323 CE, and the arrangement and packaging of its cargo provides valuable information for understanding the details of its trading activities. This paper studies the arrangement, distribution, and proportions of the discovered cargo in different zones of the ship, and analyzes its contents through observing the ways wooden containers were used. By comparing the findings with other eleventh–fourteenth-century shipwrecks in East Asian waters, the study finds that in the Sinan shipwreck, separate wooden containers were used to pack some tea-set- and altar-set-like wares suitable for the needs of the Japanese market. It is clear that the owner of the Sinan shipwreck purchased these items specifically for the needs of Japanese consumers and packed them specially in wooden cases. The Sinan shipwreck is the only existing example of a shipwreck in Asian waters from Japan’s Classical (medieval) era that provides clear evidence of having been engaged in a trade mission to serve specific customers.

The coronavirus 2019 (COVID‐19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has spread across the world and is responsible for over 1,686,267 deaths worldwide. Co‐infection with influenza A virus (IFV‐A) during the upcoming flu season may complicate diagnosis and treatment of COVID‐19. Little is known about epidemiology and outcomes of co‐infection. Data for 213 COVID‐19 patients treated at Tongji Hospital in Wuhan from January 28, 2020 to March 24, 2020 were retrospectively analyzed. Ninety‐seven of the patients (45.5%) tested positive for anti‐ IFV‐A immunoglobulin M antibodies. The clinical characteristics were described and analyzed for patients with SARS‐CoV‐2 infection only and patients with SARS‐CoV‐2/IFV‐A co‐infection. Patients with co‐infection showed similar patterns of symptoms and clinical outcomes to patients with SARS‐CoV‐2 infection only. However, an increased expression of serum cytokines (interleukin‐2R [IL‐2R], IL‐6, IL‐8, and tumor necrosis factor‐α) and cardiac troponin I, and higher incidence of lymphadenopathy were observed in patients with SARS‐CoV‐2 infection only. Male patients and patients aged less than 60 years in the SARS‐CoV‐2 infection group also had significantly higher computed tomography scores than patients in co‐infection group, indicating that co‐infection with IFV‐A had no effect on the disease outcome but alleviated inflammation in certain populations of COVID‐19 patients. The study will provide a reference for diagnosing and treating IFV‐A and SARS‐CoV‐2 co‐infection cases in the upcoming flu season.

In this work, we proposed a novel modification technique to immobilize nanoparticles by the nanopores on a boron-doped diamond surface, preventing the aggregation of nanoparticles physically and improving the stability of nanoparticles layer by the anchoring effect. All the exposed surfaces of a bare boron-doped diamond were etched into nanoporous form and larger electrochemically active surface area was obtained on the porous boron-doped diamond electrode. The carbon black nanoparticles modified porous boron-doped diamond electrode showed good selectivity to separate the oxidation potential of three molecules, but led to an extra increase in the peak current of dopamine (DA). The carbon black/Nafion modified porous diamond electrode effectively suppress the oxidation current of ascorbic acid (AA), enhancing the sensitivity of DA. The dual layer treatment enables a wide linear range, 0.1–100 μM and a low limit of detection, 54 nM for DA detection, which is almost unaffected by the excess AA and uric acid (UA). At last, real sample tests of the carbon black/Nafion modified porous diamond electrode was validated by applying to the detection of DA in human serum and dopamine hydrochloride injection, which were found to be promising at our preliminary experiments. Additionally, the fabricated carbon black/Nafion modified porous diamond electrode also demonstrated good stability and long-term functionality.

Modern radar is a typical millisecond pulse power load (MPPL), which contains a large number of power electronic devices. If the MPPL is connected to the power system, it will cause serious voltage distortion problems. The working mode of the radar pulse load will directly affect the voltage distortion. In order to analyze the influence of MPPL on the system voltage distortion, a harmonic source model of MPPL were proposed based on the switching functions. At the same time, in order to evaluate the degree of voltage distortion, an improved voltage distortion evaluation index-Waveform Relative Deviation Rate (WRDR) is proposed. The harmonic source model is based on the equivalent topology of MPPL, which can theoretically explain the cause of the sub-harmonic and inter-harmonic currents, and can reflect the influence of the parameters of MPPL on its harmonic characteristics. The simulation and experimental results prove that the harmonic source model can be used to calculate the distribution and magnitude of the harmonic current of MPPL, and to explain the cause of voltage distortion. Finally, the improved voltage distortion evaluation index is used to analyze and summarize the influence of MPPL on voltage distortion.

Functionally graded carbon nanotube-reinforced composite (FG-CNTRC) is a novel nanomaterial; the mechanical behavior of FG-CNRC has become a hot topic in the Materials Science and Engineering Science recently, thanks to its excellent mechanical and electrical properties after its fusion with matrix. In this paper, the review efforts for research progress on the modeling and analysis of FG-CNTRC structures are carried out. Firstly, the development background of FG-CNRC is presented, as well as some basic theories and main equations for mechanical analysis of FG-CNTRC structure. Then, the mechanical behaviors of FG-CNTRC beams, plates, and shells under loading conditions are comprehensively reviewed, with the emphasis on discussing the bending, buckling, and vibration behaviors of the structures. Finally, the future research orientation of the field is considered and prospected.

Janus colloidal motors (JCMs) are versatile anisotropic particles that can effectively move autonomously based on their asymmetric structures, providing unlimited possibilities for various tasks. Developing novel JCMs with controllable size, engineered nanostructure and functionalized surface properties has always been a challenge for chemists. This review summarizes the recent progress in synthesized JCMs in terms of their fabrication method, propulsion strategy, and biomedical applications. The design options, construction methods, and typical examples of JCMs are presented. Common propulsion mechanisms of JCMs are reviewed, as well as the approaches to control their motion under complex microscopic conditions based on symmetry-breaking strategies. The precisely controlled motion enables JCMs to be used in biomedicine, environmental remediation, analytical sensing and nanoengineering. Finally, perspectives on future research and development are presented. Through ingenious design and multi-functionality, new JCM-based technologies could address more and more special needs in complex environments.

In this paper, the experimental and Jacobi–Ritz method (JRM) have been adopted to analyze the forced vibration analysis of uniform and stepped circular cylindrical shells with general boundary conditions. The simply supported cylindrical shell at both ends is taken as an experimental model, and the free, steady and transient vibration characteristics of structures under hammer and fixed exciter are recorded. The results show that the results of JRM are in sensible agreement with those in experiment. In addition, the results for various boundary conditions, structural parameter are also presented. On this basis, the Newmark-[Formula: see text] integration method is adopted to realize the time domain solutions for transient vibration response, and the frequency domain results can be obtained by using Fourier transformations from time domain results. Finally, the line spectrum vibration response results of the structure are presented under the random excitation load, and the research can supply technical support for the vibration control of cylindrical shell structure.

The object of this study was to prepare activated carbons containing nitrogenous functional groups by a chemical method from nitrogen-containing raw materials. Fish (Ctenopharyngodon idellus) scales were impregnated with phosphoric acid (H3PO4) and activated at varied temperatures. The adsorption ability, structural characteristics, surface chemistry, and morphology of the activated carbons were characterized by methylene blue and iodine values, nitrogen adsorption, the Boehm method, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The total alkaline groups content of the activated carbon produced from fish scales was 0.4330 mmol/g, the total acidic groups was 1.68 mmol/g, the Brunauer–Emmett–Teller (BET) surface area was 501 cm2/g, and the total pore volume was 0.284 cm3/g. The average pore diameter was 1.94 nm under an activation temperature of 550 °C, an activation time of 1 h, and an impregnation ratio of 2. As a result of this study, nitrogenous functional groups that contained acid-base amphoteric adsorbent were produced.

Selective detection of dopamine is still a challenge due to the strong interference from ascorbic acid (AA). A hybrid dopamine electrochemical sensor was fabricated by boron-doped diamond (BDD) film co-modified with gold nanoparticles and graphite-coated nickel nanoparticles (Au-C@Ni/BDD). Highly sensitive and selective detection toward dopamine was achieved by multiple electrochemical anodic polarization treatment (EAPT) with relatively mild voltage (+ 1.6 V vs. Ag/AgCl) on Au-C@Ni/BDD electrode. Specifically, the oxidation peak separation between ascorbic acid and dopamine reached 166 mV, and the limit of detection of dopamine was as low as 0.015 μM in a linear concentration range of 0.05–100 μM with the sensitivity up to 1.99 μA μM−1 cm−2 even in the presence of interference of high-level AA. These could be ascribed to the electrocatalytically active sites and functional oxygen-containing groups of the hybrid electrodes produced by the EAPT and the excellent catalytical activity of gold nanoparticles.

Activated carbon, graphite, and GO/gelatin composite films were prepared by the blending method. The properties of composites were characterized by tensile strength (TS), elongation at break (EB), water vapour permeability (WVP), water-absorption ability, contact angle, scanning electron microscopy (SEM), and moisture at different temperatures. The properties of GO/gelatin composite films were better when each of three kinds of carbon materials were used as reinforcement phases and added into the matrix gelatin. The results showed that EB and TS of GO/gelatin composite films were both excellent. The moisture of GO/gelatin composite films was greater than the others. SEM micrographs showed that GO had better compatibility and dispersibility with gelatin than activated carbon and graphite. The water absorption of GO/gelatin composite films were low, at 15 °C and 25 °C, and the WVP was low at 35 °C. The WVP of GO/gelatin composite films was lower than the others at different temperatures. The contact angle of GO/gelatin composite films was larger than the others.

In vivo tracking or in vitro real sample analysis by electrochemistry is one of the most straight and useful methods in biosensor field. However, surface biofouling of electrodes by non-specific protein adsorption is inevitable and usually leads to a decrease in sensitivity. Here, we developed a Nafion-coated porous boron-doped diamond (NAF/pBDD) electrode with hydrophobic nanostructures to minimize the biofouling effect and selectively detect dopamine (DA). Larger active area was obtained by this procedure compared to a bare diamond electrode. The as-prepared electrode shows excellent antifouling property and enrichment capacity toward selective detection of dopamine (DA). The low background current of the BDD electrode and the enhanced signals enables a lower detection limit, 42 nmol L−1, and a wider linear range, 0.1–110 μmol L−1, for determination of DA in human serum. Additionally, the facile modified electrode demonstrated renewable property and long-term stability due to the fact that the antifouling nanostructures belong to its own.

Many bronze objects were unearthed in the capital of the Shu state in present-day Chengdu. However, only a few metallurgical studies have been carried out on those objects. This research attempts to study the alloy techniques and possible ore sources of 28 bronze objects recently excavated from the Baishoulu cemetery in Chengdu. Elemental composition and lead isotope ratios were measured, and metallographic observations were conducted. The results indicate that most objects were copper–tin–lead alloys with variable tin and lead content. The samples showed evidence of casting, as well as cold working and annealing techniques. The lead isotope data indicate that multiple lead sources were used in Baishoulu; however, the exact number is not yet known. Most of the lead sources in Baishoulu are the same as those in Zeng state bronze and Chu state bronze. In addition, some of the bronzes came from sources that were widely used in the Central Plains and surrounding regions. This new information aids in understanding the cultural interactions between Shu and other states. Moreover, some bronzes might have used local lead sources. Copper and tin sources were difficult to determine; however, the different trace elemental patterns between Baishoulu and Bayilu bronzes indicate different copper and tin sources might be used. Additionally, copper and lead may originate from different sources in the Shu state. Systematic data are necessary to disclose a possible metal source exchange network involving the Shu state in the Warring States period.