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The following article presents and corroborates an outcome space branch-and-bound algorithm for solving the general linear multiplicative programming problem (GLMPP). In this new algorithm, GLMPP is transformed into its equivalent problem by introducing auxiliary variables. To compute the tight upper bound for the optimal value of GLMPP, the linear relaxation programming problem is assembled by using bound and hull linear approximations. Furthermore, the global convergence and computational complexity of the algorithm are demonstrated. Finally, the soundness and advantage of the proposed algorithm are validated by solving a demonstrative linear multiplicative problem. [ABSTRACT FROM AUTHOR]

This article presents a self-adjustable branch-and-bound algorithm for globally solving a class of linear multiplicative programming problems (LMP). In this algorithm, a self-adjustable branching rule is introduced and it can continuously update the upper bound for the optimal value of LMP by selecting suitable branching point under certain conditions, which differs from the standard bisection rule. The proposed algorithm further integrates the linear relaxation program and the self-adjustable branching rule. The dependability and robustness of the proposed algorithm are demonstrated by establishing the global convergence. Furthermore, the computational complexity of the proposed algorithm is estimated. Finally, numerical results validate the effectiveness of the self-adjustable branching rule and demonstrate the feasibility of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The on-demand jetting of high-viscosity liquid has significant applications in fields such as electronic packaging and bioprinting. Conventional methods for high-viscosity liquid jetting often employ a needle propelling the liquid rapidly, which demands high precision in the manufacturing and assembly of the needle and nozzle, and can potentially damage biomaterials. In this study, a novel method utilizing jet tube impact for on-demand high-viscosity liquid jetting is proposed, leveraging the inherent inertia of the liquid to generate the pressure pulse necessary for on-demand jetting. This method reduces the precision requirements for the device, enables device simplification, and avoids harm to biomaterials. The feasibility of this approach for on-demand high-viscosity liquid jetting is validated through experiments, and by combining numerical simulations, the jetting mechanism is revealed and primary factors influencing jetting performance are investigated. It is found that the water hammer pressure wave induced by the liquid inertia during the sudden velocity change of the jet tube is the predominant driving force for jetting, and the peak pressure can exceed 1 MPa and the peak jet velocity can exceed 15 m/s. An increase in the jet tube impact velocity and an extension of the acceleration duration at the same impact velocity both lead to an increase in the pressure wave amplitude. In addition, a decrease in the liquid level height shortens the period of the pressure wave. These factors all have an influence on the jetting performance. This study provides a new insight and theoretical foundation for the on-demand high-viscosity liquid jetting. [ABSTRACT FROM AUTHOR]

In recent years, gallium-based liquid metal has emerged as a prominent research material in the realm of flexible electronics, owing to its exceptional electrical conductivity and deformability. The crux of developing flexible electronic devices using liquid metal as a conductive material lies in the patterning of the liquid metal. Inkjet printing technology possesses the capability to efficiently craft functional patterns by printing any inkable material. However, due to the facile oxidation of the gallium-based liquid metal surface in ambient air, leading to the formation of oxide films and the presence of high surface tension, conventional inkjet printing techniques are incapable of directly rendering liquid metal prints. This manuscript introduces a refined and remarkably efficient approach to inkjet printing utilizing the liquid metal. By deftly adjusting the interfacial tension of the liquid metal at the nozzle with ultra-low potentials, falling within the 2-V range, the achievement of on-demand, micron-scale liquid metal microdroplet ejection printing surpassing 3 kHz is brought to fruition. This article delves into unraveling the mechanisms of potential modulation on the interfacial tension of the liquid metal at the nozzle, as well as the fundamental theories pertaining to the formation and migration of liquid metal microdroplets. These insights establish a theoretical and technical foundation for the application of liquid metals in the field of electronic printing. [ABSTRACT FROM AUTHOR]

The dynamics of bubbles near a liquid–liquid interface represent a complex multiphase problem with numerous potential applications. This paper utilizes pulsed laser-induced microbubbles at the liquid–liquid interface to achieve the multi-orifice ejection of liquid metal microdroplets that are challenging to achieve with traditional inkjet printing. The study combines the expansion and collapse processes of thermal bubbles at the two-phase liquid interface with the ejection process of liquid metal droplets, unveiling the underlying mechanisms of liquid metal droplet ejection. In this work, the influence of laser parameters on the behavior of thermal bubbles at the liquid–liquid interface and the double-peak pressure effect was investigated. The impact of laser parameters on the ejection behavior of liquid metal droplets was also examined, which provides theoretical support for the wide applications of bubble dynamics at the liquid–liquid interface in the field of liquid metal inkjet printing. [ABSTRACT FROM AUTHOR]

Liquid-phase reduced metal electrodes are cleverly used in the fabrication of flexible piezoresistive sensors. Coupled with the integration of porous elastomers and composites, sensors offer permeability, flexibility, outstanding conductivity, and advanced sensing capabilities. They find applications in human physiological signal monitoring, pressure array recognition and handwriting recognition. Furthermore, sensors assisted by deep learning enable the precise recognition and correction of fitness movements. This study provides new ideas for the preparation of piezoresistive sensors and fully demonstrates their application potential in healthcare, exercise monitoring, encrypted transmission of information, and the development of intelligent wearable fitness devices. [Display omitted] • Patterned and reliable electrodes prepared based on a simple and efficient liquid-phase reduction method. • Controlled preparation of porous elastomers by the salt-molded sacrificial method. • Flexible devices with fast response and high sensitivity for multi-state sensing applications. • Deep learning assisted sensors for highly accurate recognition and correction of fitness movements. Flexibility and wearability in electronic devices gain prominence with the rise of national fitness campaigns. Among them, piezoresistive sensors stand out for their ability to accurately monitor health signals due to their high sensitivity. However, conventional metal nanoparticle ink electrodes face issues like peeling, chemical instability, and substrate limitations. This study introduces a novel method for fabricating high-performance flexible piezoresistive sensors using liquid-phase reduced metal electrodes. Integration of porous polydimethylsiloxane (PDMS) substrates with highly conductive interdigital silver electrodes (1.6 × 10−6 Ω·m) addresses conventional electrode shortcomings, offering permeability, flexibility, and outstanding conductivity. Incorporation of a graphene (GR)/carbon nanotube (CNT)/Ecoflex composite enhances sensor piezoresistive sensing capabilities, with features including high sensitivity (3.57 KPa−1), rapid response time (58 ms/72 ms), and excellent cycle stability (>10000 cycles). The sensor finds utility in various applications, including human physiological signal monitoring, pressure array recognition, and handwriting recognition. Additionally, with deep learning techniques, the system achieves accurate recognition (99.25 %) and correction (98.75 %) of diverse fitness movements, aiming to promote safer exercise practices, enhance training efficiency, and advance intelligent wearable fitness devices. [ABSTRACT FROM AUTHOR]

BACKGROUND: 10‐Hydroxy‐cis‐12‐octadecenoic acid (10‐HOE, 10‐OH C18:1), an emerging functional fatty acid, has anti‐fungal and anti‐inflammatory effects. 10‐HOE is synthesized by bacterial 10‐linoleic acid hydratase (10‐LHT) with linoleic acid as the substate. However, the characterization of 10‐LHT and its targeted synthesis of 10‐HOE have been rarely reported. In this study, the recombinant 10‐LHT from Lactiplantibacillus plantarum ZS2058 was characterized, and the biocatalysis of 10‐HOE using crude enzyme was optimized. RESULTS: The recombinant 10‐LHT catalyzed the conversion of linoleic acid (C18:2) to 10‐HOE as identified using gas chromatography‐mass spectrometry (GC–MS). It showed a molecular weight of about 70 kDa on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and was a flavin adenine dinucleotide (FAD)‐dependent enzyme. The activity of 10‐LHT was optimal at pH 6.5 and 25 °C, and it was pH‐stable but thermo‐sensitive. The optimal condition for the 10‐HOE biosynthesis using crude enzyme was 5 g L−1 linoleic acid (C18:2), 148.0 U mL−1 10‐LHT, 0.05 mmol L−1 FAD, 2% methanol and 100 mmol L−1 sodium chloride at 25 °C and pH 6.5. A conversion yield of 47.8 ± 1.5% and the corresponding 10‐HOE concentration of 2.4 ± 0.1 g L−1 were achieved at 48 h under the optimal reaction conditions. CONCLUSION: This work achieved the highest conversion yield of 10‐HOE with the highest substrate concentration, and provides some useful information for the industrial production of 10‐HOE. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this paper, by using the special structure of the real representation of quaternion matrices, the properties of the Moore–Penrose inverse of quaternion matrices and the Kronecker product of matrices, we study least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C, respectively. First we study the special structures of quaternion bihermitian and skew bihermitian matrices. Then the problem of solving the least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C can be transformed into particular real linear system using these special structures. We deduce the form of all least-squares bihermitian and skew bihermitian solutions of the quaternion matrix equation AXB = C and propose real structure-preserving algorithms to compute the minimal norm least-squares bihermitian and skew bihermitian solution. All the computation process only involve real arithmetic. Numerical examples are provided to verify the effectiveness of our algorithms. Particularly, we also propose the conditions and computation method of bihermitian and skew bihermitian solutions of quaternion matrix equation AXB = C. [ABSTRACT FROM AUTHOR]

This article proposes an efficient global algorithm for solving general linear multiplicative programming problem (GLMP). The new algorithm combines the quadratic convex relaxation problem, adaptive branching rule, region reduction technique and branch-and-bound scheme. Firstly, a transformation technique can transform GLMP into a non-convex quadratic program with quadratic and linear constraints. The non-convexity parts of the equivalent problem are addressed by employing secant lines, so that a quadratic convex relaxation problem is structured. Secondly, we introduce the adaptive branching rule to improve the upper bound of the optimal value. Thirdly, the convergence of the proposed algorithm is analyzed and its worst-case complexity is provided. Finally, numerical experiments demonstrate the efficiency and advantage of the proposed algorithm for obtaining the global ɛ -optimal solutions of test instances. • A novel branch-and-bound algorithm is presented for globally solving GLMP. • The algorithm integrates QCR, adaptive branching rule, region deletion technique and BB scheme. • The global convergence and computational complexity of the algorithm are reported. • Numerical results show the effectiveness of the algorithm to obtain an optimal solution of GLMP. [ABSTRACT FROM AUTHOR]

• The mechanism of action of thermal bubbles at the solid–liquid interface was studied for the first time. • Unveiling the underlying mechanisms of liquid metal droplet ejection. • The potential of utilizing this technology to achieve multi-orifice liquid metal jetting was demonstrated. In this work, we introduced the pulsed laser-driven liquid metal arrayed printing technology. This study harnesses sub-millimeter-sized rapidly expanding bubbles generated by nanosecond pulsed laser irradiation at the solid–liquid interface as the power source for liquid metal printing, enabling efficient arrayed jetting printing of liquid metal. Utilizing high-speed imaging technology, this study investigates the expansion process of bubbles induced by nanosecond pulsed lasers at the solid–liquid interface and the jetting process of liquid metal, thereby revealing the mechanism of liquid metal jet ejection. The study systematically examines the influence of laser parameters on the jetting behavior of liquid metal, laying a theoretical and technical foundation for applications such as patterned printing in the field of liquid metal. This technology holds significant engineering implications for further advancing the application of liquid metal in fields such as flexible electronics and printed electronics. [ABSTRACT FROM AUTHOR]

Quaternion equality constrained least squares (QLSE) problems have attracted extensive attention in the field of mathematical physics due to its applicability as an extremely effective tool. However, the knowledge gap among numerous QLSE problems has not been settled now. In this paper, by using quaternion SVD (Q-SVD) and the equivalence of the QLSE problem and Karush-Kuhb-Tucker (KKT) equation, we obtain some equations about the matrices in the general solution of the QLSE problem. Using these equations, an equivalent form of the solution of the QLSE problem is obtained. Then, applying the special structure of real representation of quaternion, we propose a real structure-preserving algorithm based on Q-SVD. At last, we give numerical example, which illustrates the effectiveness of our algorithm. [ABSTRACT FROM AUTHOR]

Form grinding is the finishing process of the cycloid gear of RV reducer. In order to avoid the tooth surface burn of the cycloid gear during the grinding process and improve the grinding efficiency, the heat distribution ratio and the convection heat dissipation coefficient during the grinding process are calculated. The computer simulation software ANSYS 17.0 is used to calculate the instantaneous temperature field of the tooth surface during the grinding process of the cycloid gear. The distribution of the instantaneous temperature field of the tooth surface along the axial of the gear is obtained. According to the characteristics of the YK7350B gear grinding machine, the grinding process parameters is reasonably selected, and the grinding experiment is carried out. The metallographic structure of the burned section of the experimental part was observed by the ProgRes C5 metallographic measuring instrument to verify the simulation results. The research is beneficial to predict the temperature field distribution of the tooth surface of the cycloid gear and select the grinding process parameters reasonably. [ABSTRACT FROM AUTHOR]

Quaternion equality constrained least squares problem is an extremely effective tool in studying quantum mechanics and quantum field theory. However, the computation of the quaternion equality constrained least squares problem is extremely complex. In this paper, we first prove that quaternion equality constrained least squares problem is equivalent to weighted quaternion least squares problem when the parameter τ→+∞. Then, for weighted quaternion least squares problem, applying the special structure of real representation of quaternion, we propose real structure–preserving algorithm to obtain the solution of quaternion equality contained least squares problem. At last, we give numerical examples to illustrate the effectiveness of our method. [ABSTRACT FROM AUTHOR]

Objective: Muscle dysfunction caused by repetitive work or strain in the neck region can interfere muscle responses. Muscle dysfunction can be an important factor in causing cervical spondylosis. However, there has been no research on how the biomechanical properties of the upper cervical spine change when the suboccipital muscle group experiences dysfunction. The objective of this study was to investigate the biomechanical evidence for cervical spondylosis by utilizing the finite element (FE) approach, thus and to provide guidance for clinicians performing acupoint therapy. Methods: By varying the elastic modulus of the suboccipital muscle, the four FE models of C0-C3 motion segments were reconstructed under the conditions of normal muscle function and muscle dysfunction. For the two normal condition FE models, the elastic modulus for suboccipital muscles on both sides of the C0-C3 motion segments was equal and within the normal range In one muscle dysfunction FE model, the elastic modulus on both sides was equal and greater than 37 kPa, which represented muscle hypertonia; in the other, the elastic modulus of the left and right suboccipital muscles was different, indicating muscle imbalance. The biomechanical behavior of the lateral atlantoaxial joint (LAAJ), atlanto-odontoid joint (ADJ), and intervertebral disc (IVD) was analyzed by simulations, which were carried out under the six loadings of flexion, extension, left and right lateral bending, left and right axial rotation. Results: Under flexion, the maximum stress in LAAJ with muscle imbalance was higher than that with normal muscle and hypertonia, while the maximum stress in IVD in the hypertonic model was higher than that in the normal and imbalance models. The maximum stress in ADJ was the largest under extension among all loadings for all models. Muscle imbalance and hypertonia did not cause overstress and stress distribution abnormalities in ADJ. Conclusion: Muscle dysfunction increases the stress in LAAJ and in IVD, but it does not affect ADJ. [ABSTRACT FROM AUTHOR]

Generating individual, small droplets offers unique possibilities for various applications where precise volume and concentration control are necessary. This paper presents a systematic method for generating ultra-small droplets based on a controllable meniscus break-up procedure. The method utilizes two nozzles that are connected to a computer-controlled syringe through a three-way junction. A syringe is used to extrude the liquid from both orifices until they are connected by a liquid meniscus. Next, draining the liquid out of the meniscus and back into the nozzle will cause the meniscus to thin, which will ultimately result in its break-up and the formation of one small droplet. Both experimental and theoretical studies are presented to demonstrate the validity of the proposed method. It is shown that droplets with volumes from femtoliters to nanoliters can be generated. [ABSTRACT FROM AUTHOR]

A novel spirobifluorene derivative SPF-TMS , which containing dithioacetal groups and triphenylamine units, was synthesized. The probing behaviors toward various metal ions were investigated via UV/Vis absorption spectra as well as one-photon fluorescence changes. The results indicated that SPF-TMS exhibits high sensitivity and selectivity for mercury ions. The detection limit was at least 8.6 × 10 −8 M, which is excellent comparing with other optical sensors for Hg 2+ . When measured by two-photon excited fluorescence technique in THF at 800 nm, the two-photon cross-section of SPF-TMS is 272 GM. Especially, upon reaction with mercury species, SPF-TMS yielded another two-photon dye SPF-DA . Both SPF-TMS and SPF-DA emit strong two-photon induced fluorescence and can be applied in cell imaging by two-photon microscopy. [ABSTRACT FROM AUTHOR]

Electric arc machining (EAM), which shares the similar principle as electric discharge machining (EDM), has attracted extensive research interest in the area of electrical machining due to its extremely high material removal rate (MRR). However, the material removal mechanisms of this technology were rarely reported. In this paper, the energy distribution and material removal mechanisms of EAM were systematically investigated. It was found that, compared with the traditional electric discharge machining (EDM), the energy efficiency (the ratio of energy used to remove material from workpiece with regard to the total energy distributed into workpiece) and removal efficiency (the volume ratio of removed material with regard to the total melted material in the workpiece) of EAM is much higher. The removal efficiency of EAM can be as high as 90% whereas it is only about 5% in the case of traditional EDM and no more than 20% in the case of micro EDM. In this work, the energy distribution, material removal mechanisms and characteristics of EAM were deeply investigated and reasons behind the high energy and removal efficiency were explained. Some insightful views were provided by this work, such as materials were removed during the whole discharge, the thickness of recast layer was almost the same as the traditional EDM, the expansion speeds of the discharge generated bubble and ejective debris were calculated. [ABSTRACT FROM AUTHOR]

Understanding how terrestrial ecosystems would respond to future climate change can substantially contribute to scientific evaluation of the interactions between vegetation and climate. To reveal the future climate impacts might on the nature and magnitude of global vegetation, the spatiotemporal distribution and net primary productivity (NPP) of global terrestrial biomes and their dynamics in this century were quantitatively simulated and compared by using the improved Comprehensive and Sequential Classification System and the segmentation model. The 33 general circulation models under the four scenarios of Representative Concentration Pathways (RCPs) were utilized to simulate the future climate change. The multi-model ensemble results showed that at the global scale, the distribution of forests and deserts would expand by more than 2% and 4% over this century, respectively. By contrast, more than 11% of grassland regions would shrink. Despite the considerable differences in the simulated responses of the biomes, the poleward movement or expansion of temperate forest were prominent features across all the scenarios. Meanwhile, the terrestrial NPP was projected to increase by 7.44, 9.51, 9.46, and 12.02 Pg DW·a − 1 in 2070s relative to 1970s in the RCP2.6, RCP4.5, RCP6.0, and RCP8.5, respectively. The largest NPP decrease would occur in tundra & alpine steppe. NPP in the Tropical Zone, the North Temperate Zone, and the North Frigid Zone was estimated to increase in this century, whereas NPP in the South Temperate Zone was projected to decrease slightly across all scenarios. Overall, ecosystems in the mid-/high latitudes would be more vulnerable to future climate change in terms of distribution ranges and primary productivity despite the existing uncertainties. Some vegetation would benefit from the warmer and wetter climate. However, most of these plants would suffer and experience irreversible changes, particularly in the northern hemisphere. [ABSTRACT FROM AUTHOR]

A novel fluorescent probe SPF-TSA was prepared by introduction of triphenylamine and dithioacetal groups on the respective biphenyl branches of 9,9′-spirobifluorene. The probing behaviors toward metal ions and pH variations were investigated via UV/Vis absorption spectra as well as one-photon fluorescence changes. SPF-TSA exhibits high sensitivity and selectivity for mercury ions and could be used to detect mercury ions even by naked eye. The detection limit of SPF-TSA for Hg 2+ is at least 2.6 × 10 −8 M, which is excellent comparing with other optical sensors for Hg 2+ . SPF-TSA showes significantly pH-dependent spectral properties within the acidic pH-range. Especially, the p K a value of SPF-TSA is close to 6.0, which is critical for precisely assessing the acidic environments of some organelles (pH 4.5–6.8). The two-photon absorption cross-section value of SPF-TSA at 800 nm is 248 GM. SPF-TSA emits strong two-photon induced fluorescence and the emission wavelength change before and after addition of Hg 2+ was found to be up to140 nm. Cell imaging studies demonstrate that SPF-TSA enables fluorescence imaging of both the probe and mercury ions in cells by two-photon microscopy. [ABSTRACT FROM AUTHOR]

Two fluorophores, SPF-TNS and SPF-TBB , with electron-rich triphenylamine groups and Ag + receptor units on the respective biphenyl branches of 9,9′-spirobifluorene were synthesized. They exhibit strong one- and two-photon excited fluorescence, and the two-photon absorption cross-section values are 665 GM for SPF-TNS and 355GM for SPF-TBB . The probing behaviors toward metal ions were investigated via UV/Vis absorption spectra as well as one-photon fluorescence changes. The results indicated that SPF-TNS and SPF-TBB exhibit distinct fluorescent quenching in the presence of silver ions that can be used for highly sensitive and selective naked-eye detection of Ag + . The one-photon excited fluorescence of SPF-TBB can be made to measure water content of organic solvents. The detection limits were calculated to be 0.04% for THF and 0.03% for 1,4-dioxane. The two-photon scanning microscopy experiments suggest that SPF-TNS is a promising label potentially applicable for the tracking of biomolecules. [ABSTRACT FROM AUTHOR]

The insula is a region that integrates interoception and drug urges, but little is known about its role in behavioral addiction such as internet addiction. We investigated insula-based functional connectivity in participants with internet gaming disorder (IGD) and healthy controls (HC) using resting-state functional MRI. The right and left insula subregions (posterior, ventroanterior, and dorsoanterior) were used as seed regions in a connectivity analysis. Compared with the HC group, the IGD group showed decreased functional connectivity between left posterior insula and bilateral supplementary motor area and middle cingulated cortex, between right posterior insula and right superior frontal gyrus, and decreased functional integration between insular subregions. The finding of reduced functional connectivity between the interoception and the motor/executive control regions is interpreted to reflect reduced ability to inhibit motor responses to internet gaming or diminished executive control over craving for internet gaming in IGD. The results support the hypothesis that IGD is associated with altered insula-based network, similar to substance addiction such as smoking. [ABSTRACT FROM AUTHOR]

In this study, the dehydration of water-in-oil emulsion subjected to an electric field was investigated both experimentally and via computer simulation. The time evolution of the droplets subjected to an electric field was investigated using optical microscopy. We also implemented a computer simulation of the dynamic behavior of the droplets resulting from the balance of forces applied on them. The probability of coalescence between droplets as well as coalescence between droplets and the water/oil interface was also investigated. Thus, the behavior of the droplets could be observed more directly, and the problem could be solved stochastically and mathematically. Through adjustment of the values of the two coalescence probabilities, the simulated results could accurately represent the actual process. [ABSTRACT FROM AUTHOR]

Abstract: This work proposed a novel method of determining the energy distribution and plasma diameter of EDM. The energy distribution and plasma diameter were determined by comparing the boundary of the melted material in the crater which was obtained by metallographic method and the isothermal curve of the thermal-physical model using finite element method (FEM). The results of this work indicated that the expansion of the plasma diameter must be taken into consideration in order to be more consistent with the actual EDM process. With this method, the energy distribution and plasma diameter in different dielectrics with different polarities were investigated. Comparison between the results of this work and the previously reports showed that the energy distributed into workpiece and plasma diameter can be determined by this new method. [Copyright &y& Elsevier]

Abstract: Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of T. chinensis var. mairei. The T. chinensis var. mairei cp genome is 129,513bp in length, with 113 single copy genes and two duplicated genes (trnI-CAU, trnQ-UUG). Among the 113 single copy genes, 9 are intron-containing. Compared to other land plant cp genomes, the T. chinensis var. mairei cp genome has lost one of the large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperm such as Cycas revoluta and Ginkgo biloba L. Compared to related species, the gene order of T. chinensis var. mairei has a large inversion of ~110kb including 91 genes (from rps18 to accD) with gene contents unarranged. Repeat analysis identified 48 direct and 2 inverted repeats 30bp long or longer with a sequence identity greater than 90%. Repeated short segments were found in genes rps18, rps19 and clpP. Analysis also revealed 22 simple sequence repeat (SSR) loci and almost all are composed of A or T. [Copyright &y& Elsevier]

Highlights: [•] Material removal characteristics in five different dielectrics were investigated. [•] Complete geometry of craters was precisely determined by metallographic methods. [•] Evolution of discharge generated bubble was investigated by computer simulation. [•] Material removal characteristics were significantly affected by bubble pressure. [ABSTRACT FROM AUTHOR]

The evolution of bubble generated by electrical discharge in sinking electrical discharge machining (EDM) occurs in a very short time period and in a very narrow space, thus making both observation and theoretical analysis extremely difficult. For this reason, the role of the discharge-generated bubble during the material removal process in sinking EDM has not to be understood very clearly. In this paper, the evolution process of the discharge-generated bubble was simulated in three dimensions and the influence of inter-electrode distance was studied. It was found that the evolution of the discharge-generated bubble was significantly affected by the inter-electrode distance. Smaller inter-electrode distances can contribute to a larger pressure and expansion velocity of the bubble as well as a larger force applied on the tool electrode and workpiece. The experimental results showed that the geometry characteristics of the crater were also significantly affected by inter-electrode distance. A smaller inter-electrodes distance can contribute to a larger volume of both melted and removed materials. The simulation results were discussed by relating to the results of single-pulse discharge experiments; some insightful views about the material removal mechanism of EDM were presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a new type of sinking electric discharge machining (EDM) dielectric-water-in-oil (W/O) emulsion is proposed, and the machining characteristics of W/O emulsion are investigated by comparing with that of kerosene. In the experiments, machining parameters such as the dielectric type, peak current, and pulse duration are changed to explore their effects on machining performance, including the material removal rate (MRR), relative electrode wear rate (REWR), and surface roughness. Experimental results revealed that W/O emulsion could be used as the dielectric fluid of sinking EDM and adopting long pulse duration and large peak current could lead to obtaining higher MRR than kerosene. Compared with kerosene, W/O emulsion is observed to cause lower carbon adhered to the electrode surface. Therefore, its REWR is higher. Statistics of the discharge waveform show that more stable discharge processes can be obtained by using W/O emulsion compared with kerosene. Furthermore, W/O emulsion is more economical and more environmentally friendly than kerosene, and it could be an alternative to kerosene in sinking EDM application. [ABSTRACT FROM AUTHOR]

Adsorption of surfactants at water-oil interfaces is of great importance in the coalescence of drops and stability of emulsions. In this work, we have studied the adsorption of nonionic surfactants Span 80 at water-oil interfaces and its influence on the drop rest phenomenon and W/O emulsion stability in a pulsed DC electrical field. The variation of interfacial tension with the concentration of surfactant was studied and the data were fitted using a surface equation of state derived from the Langmuir adsorption isotherm. A stochastic model for coalescence was used to fit the coalescence time distributions. The significance of the model parameters was discussed. The stability of the emulsion was evaluated by conductivity methods. The researches in this article indicated that both of the rest time distribution of the drops at the interface and stability of the emulsion in the electrical field was significantly affected by surfactant concentration. [ABSTRACT FROM AUTHOR]

The influence of several factors on the electrostatic dehydration process of water-in-model oil emulsions in high-frequency electrical field has been studied using conductivity technique. The ascending and the descending periods of the observed conductivity versus time curves were fit to sigmoid and power function, respectively, which revealed the model parameters that were used to quantify anew dehydration efficiency (DE) index. Experiments results shown that not only water content, surfactant concentration, salt concentration in the aqueous phase and temperature but also homogenization were all found to play a non-negligible role in the electrostatic dehydration process. [ABSTRACT FROM AUTHOR]

Abstract: Although the concept of optimum frequency had been proposed many years due to the various dielectrics, electrical and rheological properties of the water-in-oil (W/O) emulsion, the frequency of the pulsed DC electrical field was still kept constant during the electrical dehydration process in most of the industry application up to now. Taking into consideration of the increment of the droplets’ diameter and variation of various dielectric and rheological properties of the dispersion system during the dehydration process, the dehydration efficiency of pulsed DC electrical field with changing frequency during the dehydration process was investigated in this paper. The results showed that with appropriate combination of the frequencies, the dehydration efficiency of the pulsed DC electrical field can be significantly improved. [Copyright &y& Elsevier]

Abstract: Electrical discharge machining (EDM) caused a recast layer to form at the machined surface of the workpiece. The characteristics of the recast layer have a great relationship with the type of dielectric. The research work in this paper aims to acquire a profound knowledge of the recast layers of a surface machined by sinking EDM using water-in-oil (W/O) emulsion as dielectric. Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrograph (EDS) and micro hardness analysis were performed. The characteristics of the recast layer formed in W/O emulsion were investigated by comparing them with those of the recast layer formed in kerosene and de-ionized water dielectric. It was found that the recast layer formed in W/O emulsion exhibited larger surface roughness, thickness and micro hardness compared with that formed in kerosene and de-ionized water. Both carbide and oxide were detected in the recast layer formed in W/O emulsion whereas only carbide was detected in the recast layer formed in kerosene. Due to the higher supersaturation of gases in the melted material, the recast layer formed in W/O emulsion was found to possess more micro-voids than that formed in kerosene and de-ionized water. [Copyright &y& Elsevier]

Abstract: The influence of several operational variables on the electrostatic separation of water-in-oil emulsions is investigated in a Perspex cell equipped with a high-frequency pulsed DC generator using conductivity technique. The ascending and the descending periods of the observed conductivity vs. time curves were fit to the sigmoid and power function, respectively, which revealed the model parameters that were used to quantify dehydration efficiency (DE). Experiment results show that DE increases with decreasing inter-electrode distance, and at a given inter-electrode distance, DE increases with decreasing frequency. Furthermore, at a given pulse interval, DE increases with increasing pulse duration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interaction between COS 2-6 (oligomers of glucosamine) and BSA was analyzed. • COS 2 and COS 3 were enriched in COS 2-6 -BSA precipitate. • The binding-site number of COS 2-6 -BSA was calculated as about 1. • Electrostatic and hydrophobic effects were the main forces for COS 2-6 -BSA complex. • The binding of COS 2-6 to BSA was weak and selective. The interaction between chitooligosaccharides (COS 2-6) and bovine serum albumin (BSA) is worthy of investigation, which provides support for improving the physical properties (gelling, foaming, and emulsifying) of food proteins via COS addition and in vivo research on COS bioactivity. Component analysis indicated that COS 2 and COS 3 were enriched in the COS 2-6 -BSA precipitate. The fluorescence binding constant (1.73 × 103 M−1), Δ G of isothermal titration calorimetry (-6.7 kJ/mol), and the predicted Δ G of molecular docking (−10 to −5 kJ/mol) confirmed the weak interaction of COS 2-6 -BSA. Quartz crystal microbalance dissipation and molecular docking indicated that electrostatic and hydrophobic interactions were the main stabilization forces. Molecular docking showed that the predicted Δ G of COS 2-6 to BSA decreased with the increasing degree of polymerization. This work clarified the weak and selective interaction between COS 2-6 and BSA via various methods, which is useful for the food application of COS. [ABSTRACT FROM AUTHOR]

Inkjet printing technology has played an irreplaceable role in life science, precision manufacturing, and other frontier fields in recent years. However, the further development of this technology is limited by the fact that its printing resolution is difficult to raise to a higher level. The emerging satellite droplet printing technology offers a new approach for inkjet printing to break through the bottleneck of printing resolution limitations. In this paper, a symmetrical satellite droplet printing strategy is proposed. The effects of the geometric parameters of the satellite droplet generating device, the physical properties of the ink, and the operating parameters on the liquid bridge breakup process and the size of the satellite droplet are systematically studied. The phase field method and adaptive mesh refinement strategy are applied to solve the two-dimensional symmetrical model. The results indicate that the length of the liquid bridge, the radius of the bridge, the viscosity of the ink, and the drainage velocity are all positively correlated with the satellite droplet size, while the surface tension coefficient has a negative correlation with the satellite droplet size. Furthermore, the three-phase contact line at the orifice end will slip toward the center if the initial radius of the liquid bridge is quite large. Based on these investigations and discussions, a corresponding effective working space for satellite droplet printing is obtained, which lays the foundation for the popularization and further development of satellite droplet printing technology. [ABSTRACT FROM AUTHOR]

To mitigate the grassland degradation in the Mongolian Plateau (MP), both China and Mongolia governments have carried out a series of new policies and ecological projects. However, the effect of such restoration measures on the productivity of grassland in the MP under different political systems remains unclear. Here we study the effects of land use and land cover change, human activities and climate change on the net primary productivity (NPP) of grassland in Mongolia (MG) and Inner Mongolia (IM) from 2001 to 2014. Results showed that the area of grassland increased in both MG and IM, accounted for 4.45 × 104 and 10.31 × 104 km2, respectively. The extended grassland contributed 4.34 × 108 Gg C (Gg = 109 g) to the total NPP, while the loss of grassland led to a decrease of 0.19 × 108 Gg C. The total NPP of grasslands in 2014 increased about 17.88% and 30.49% respectively in MG and IM since 2001. Specifically, IM exhibited a higher increase in land converted NPP than MG. The area of grassland restoration in IM and MG accounted for 90.21% and 81.45%, respectively, indicating that the grassland of the MP was restored. Although human activity was the dominant factor on grassland degradation, which was accounted for 9.79% and 18.55% in IM and MG, it has a positive effect on most of the grassland NPP in the MP. Overall, policy measures and ecological projects in IM brought a more positive effect compared with that in MG. Unlabelled Image • Land use and cover change (LUCC) as one of driving factors was quantified. • Inner Mongolia had a higher increase of land conversion NPP than Mongolia. • Grasslands in most areas of the Mongolian Plateau show a recovery trend. • Human activities are still the dominant factor in promoting degradation in the MP. [ABSTRACT FROM AUTHOR]

Drop-on-demand inkjet technology has played an irreplaceable role in various cutting-edge fields in the gaseous environment, which relies on the acoustic waves in the channel to dispense droplet. The droplet diameter is about 20–100 µm and is difficult to be further reduced. For the emerging high-resolution inkjet technology in a liquid environment based on the confined interface vibration triggered by acoustic waves in the printhead, the droplet size can be 10 times smaller than the orifice, which can also be facilely regulated. However, the residual vibrations of the confined interface will dispense secondary droplets when the stimulation is significant, interfering the uniformity of the printing results. Herein, a strategy that can regulate the interface behavior by manipulating the acoustic waves in the channel is proposed, which can achieve a significant main vibration while the residual vibrations are effectively suppressed. A mathematical model is constructed based on the experimental phenomenon to explain how the interface behavior is regulated. The influence of echo time on the interface vibrations, the mechanisms of how the residual vibrations affect the subsequent main vibration and primary droplet are revealed. This work provides a theoretical guidance for regulating droplet size and improving the printing resolution of inkjet in a liquid environment by regulating the acoustic waves in the channel, and demonstrates its practical application potential. [ABSTRACT FROM AUTHOR]

Epidermal leaf waxes of terrestrial higher plants have been widely utilized for the reconstructions of paleoenvironment and paleoclimate in peat deposits. In this study, specimens of four plant species growing in both peatland and non-peatland habitats were retrieved to compare their molecular, carbon (δ13C) and hydrogen (δ2H) isotopic compositions of leaf wax n-alkanes from a closed subalpine basin in Central China. Three of the four species show quite higher total concentrations of n-alkanes in the relatively dry non-peatland setting than in the peatland. In addition, the δ2H values of long-chain n-alkanes are generally less depleted in the peatland and are comparable among different plant species, which is interpreted as the influence of inundation condition and the possible limited supply of photosynthetic products. This study reveals different patterns of plant wax molecular and isotopic compositions between peatland and the surrounding non-peatland conditions, and confirms the paleoenvironmental potential of leaf wax ratios on the peat sequences. [ABSTRACT FROM AUTHOR]

The design and implementation of a real-time ultra-high definition (UHD) multiview glasses-free 3D display system always suffer from the high transmission bandwidth, high memory cost, and high computational complexity. This paper presents a glasses-free 3D display system based on depth-image-based rendering (DIBR) technique by solving these problems. It can convert a V + D video (RGBD) stream in real time to a multiview representation suitable for a multiview autostereoscopic display. As V + D video format is used for the system, the transmission bandwidth is reduced. For the memory cost, we introduce an asymmetric shift-sensor camera setup to avoid external memory usage and reduce the storage requirement of multiviews. For the computational complexity, as our camera setup ensures that all the virtual views can be generated with the same DIBR algorithm, the computational complexity is reduced. In addition, we simplify the view fusion method so as to rearrange the subpixels from multiviews with lower complexity to form a single glasses-free 3D image. Moreover, we propose a hardware architecture for the system and implement it using field programmable gate array. Simulation results show that our system can support the UHD V + D videos for an 8-view glasses-free 3D display. Performance evaluation results show that the proposed system can provide reasonably good stereoscopic image quality if appropriate parameters of the system are applied. [ABSTRACT FROM AUTHOR]

Background: Snub-nosed monkeys are highly endangered primates and their population continues to decline with the habitat fragmentation. Artificial feeding and breeding is an important auxiliary conservation strategy. Studies have shown that changes and imbalances in the gut microbiota often cause gastrointestinal problems in captive snub-nosed monkeys. Here, we compare the gut microbiota composition, diversity, and predicted metabolic function of three endangered species of snub-nosed monkeys (Rhinopithecus bieti, R. brelichi, and R. roxellana) under the same captive conditions to further our understanding of the microbiota of these endangered primates and inform captive conservation strategies. 16 S rRNA gene sequencing was performed on fecal samples from 15 individuals (R. bieti N = 5, R. brelichi N = 5, R. roxellana N = 5). Results: The results showed that the three Rhinopithecus species shared 24.70% of their amplicon sequence variants (ASVs), indicating that the composition of the gut microbiota varied among the three Rhinopithecus species. The phyla Firmicutes and Bacteroidetes represented 69.74% and 18.45% of the core microbiota. In particular, analysis of microbiota diversity and predicted metabolic function revealed a profound impact of host species on the gut microbiota. At the genus level, significant enrichment of cellulolytic genera including Rikenellaceae RC9 gut group, Ruminococcus, Christensenellaceae R7 group, UCG 004 from Erysipelatoclostridiaceae, and UCG 002 and UCG 005 from Oscillospiraceae, and carbohydrate metabolism including propionate and butyrate metabolic pathways in the gut of R. bieti indicated that R. bieti potentially has a stronger ability to use plant fibers as energy substances. Bacteroides, unclassified Muribaculaceae, Treponema, and unclassified Eubacterium coprostanoligenes group were significantly enriched in R. brelichi. Prevotella 9, unclassified Lachnospiraceae, and unclassified UCG 010 from Oscillospirales UCG 010 were significantly enriched in R. roxellana. Among the predicted secondary metabolic pathways, the glycan biosynthesis and metabolism had significantly higher relative abundance in the gut of R. brelichi and R. roxellana than in the gut of R. bieti. The above results suggest that different Rhinopithecus species may have different strategies for carbohydrate metabolism. The Principal coordinate analysis (PCoA) and Unweighted pair-group method with arithmetic mean (UPGMA) clustering tree revealed fewer differences between the gut microbiota of R. brelichi and R. roxellana. Correspondingly, no differences were detected in the relative abundances of functional genes between the two Rhinopithecus species. Conclusion: Taken together, the study highlights that host species have an effect on the composition and function of the gut microbiota of snub-nosed monkeys. Therefore, the host species should be considered when developing nutritional strategies and investigating the effects of niche on the gut microbiota of snub-nosed monkeys. [ABSTRACT FROM AUTHOR]

Objectives: Our previous studies showed that strontium (Sr)‐modified sand‐blasted, large grit, acid etched titanium surface (Sr‐SLA) is beneficial for osseointegration; however, the supporting mechanisms have not been explored in detail. Materials and Methods: Whole‐transcriptome RNA sequencing of peri‐implant bone tissue was performed, and CDH2 was selected as a key mediator of Sr‐SLA‐mediated osseointegration. To test this hypothesis, a lentivirus‐mediated vector targeting the silencing of the CDH2 gene was used in mesenchymal stem cells (MSCs) prior to seeding on Ti substrates. The effects of CDH2 interference on MSCs vitality, differentiation, and β‐catenin signaling activity were evaluated. In vivo, a recombinant adeno‐associated virus 9 vector carrying an artificial siRNA that target CDH2 (AAV9‐CDH2i) was intravenously injected in mice, followed by tibial surgery with implant placement. Osseointegration were monitored using micro‐CT analysis. Results: CDH2 expression in MSCs on Sr‐SLA was higher than the control group, which was in parallel with the enhanced cell migration, adhesion, and upregulation of early osteogenic markers. Knocking down CDH2 in MSCs resulted in decreased cell viability and osteogenic differentiation, and the elevated biocompatibility and osteoinductive effect of Sr‐SLA were greatly diminished. Surprisingly, Sr‐SLA‐induced upregulation of CDH2 was not followed by restriction of β‐catenin signaling because Sr‐SLA also promoted the expression and nuclear translocation of β‐catenin. Systemic administration of AAV9‐CDH2i effectively knocked down CDH2 expression in bone marrow cells, and in turn, inhibited bone formation induced by Sr‐SLA. Conclusions: The results indicated that CDH2 is required for Sr‐SLA‐mediated bone regeneration, which reveals a new mechanism to explain the osteoinductive effect of Sr‐SLA. Thus, biomaterial modifications targeting CDH2 may help improve early osseointegration and bone healing. [ABSTRACT FROM AUTHOR]

Micro piezoresistive pressure sensor has become one of the most widely used microelectromechanical systems devices due to its high sensitivity, low cost and simple fabrication. For developing piezoresistive pressure sensor, one of the most important considerations is the configuration (structure) of the diaphragm. Although various types of diaphragm structure have been proposed, they are often designed intuitively, and thus to a large extent they depend on the designers' intuition and experience. This paper presents a systematic approach for designing diaphragm structures for piezoresistive pressure sensor by using topology optimization. The design problem is treated as a three dimensional topology optimization problem with design dependent loads in which the dependence is regarded due to transmissible loads. The objective is to minimize the mean compliance to achieve high linearity. Several geometrical constraints are developed to achieve high sensitivity. The design problem is solved by using the popular SIMP (Solid Isotropic Material With Penalization) method. A number of design examples are used to demonstrate the ability of the procedure to generate nonintuitive diaphragm structures. Solutions obtained from this procedure are compared with diaphragms with other configurations reported in the literature. [ABSTRACT FROM AUTHOR]

Efficient and facile generation of tiny droplets is critical to many cutting-edge applications, such as flexible electronic skin, customized circuits, and micro-electro-mechanical systems. However, conventional piezoelectric inkjet printing techniques show more prominent problems of high driving voltage and relatively low printing frequency. Here, a novel principle for high-throughput droplet dispensing was proposed based on the resonance of the liquid column within the glass capillary. The mechanisms of this high-throughput piezoelectric droplet dispensing technique were studied both experimentally and theoretically. It is demonstrated experimentally that the resonance frequencies of different orders of the liquid column in the capillary fit perfectly with the theoretical value. It is further demonstrated that when the working frequency is close to the resonant frequency of piezoelectric ceramic, droplets can be ejected out by a driving voltage as low as 1 V. This ultra-low driving voltage and power consumption make this dispenser compatible with various digital transistor–transistor logic or complementary metal–oxide–semiconductor drive circuits without any power amplifier. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of fruit and vegetable intake on gut microbiota using a mouse model of metabolic syndrome (MS) induced by a high‐fat diet. Forty‐eight male mice were randomly divided into four groups, control group (C), high‐fat diet‐fed model group (H), high fat plus low intake of fruits and vegetables diet‐fed group (H.LFV), high fat plus high intake of fruits and vegetables diet‐fed group (H.HFV), and each group were fed for 60 days. During the experiment, mouse body weights were recorded and fecal samples were collected. Cetyltrimethyl ammonium bromide (CTAB) method was used to extract fecal bacterial DNA, and the purity and concentration of the DNA were detected by electrophoresis. DNA samples underwent PCR amplification (primers in 16 S V4 (515F and 806R)). Raw sequencing data were processed, and sample complexity and multiple‐sample comparisons were investigated. Mouse organ coefficient, serum lipid levels, fecal TC (total cholesterol) and TBA (total bile acid) levels, and hepatic glutathione and malondialdehyde levels were determined. Compared to the H group, the fecal TC and TBA levels decreased significantly in the H.HFV group (p <.05), and hepatic glutathione and malondialdehyde levels decreased significantly in both H.LFV and H.HFV groups (p <.05). Decreased abundance of Firmicutes, Burkholderiales, Syntrophomonas, and Pseudomonadales in gut microbiota was observed in H.LFV and H.HFV groups compared to the H group. The Anosim results showed significant differences in pairwise comparison between groups. The linear discriminant analysis effect size (LEfSe) results showed that k_bacteria not only exhibited statistically differences between H and C groups but also among H.LFV, H.LFV, and H groups, and hence, could be used as a biomarker between groups. To sum up, fruit and vegetable powder could increase the fecal excretion of TC and TBA, and the antioxidant capacity in C57BL/6N mice. Meanwhile, the mechanism that fruit and vegetable powder could prevent MS in C57BL/6N mice was related to the decreased abundance of gut microbiota, including Firmicutes, Syntrophomonadales, and Pseudomonadales. Hence, fruit and vegetable powder could be used as a recommended food to regulate gut microbiota and prevent the occurrence of MS‐related diseases. [ABSTRACT FROM AUTHOR]

Background: Several clinical trials have recently been conducted to elucidate the effectiveness of photofunctionalization. The aim of this review was to systematically analyze the clinical effects of photofunctionalization on implant stability and marginal bone loss (MBL). Methods: An electronic search in four databases and a manual search were conducted in September 2022. Randomized controlled trials (RCTs), clinical controlled trials (CCTs), and cohort and case-control studies evaluating the effects of photofunctionalization on implant stability or marginal bone loss (MBL) in humans were included. The methodological quality assessment using RoB 2.0 and the ROBINS-I tool was performed based on different study designs. Results: Seven studies were included for a qualitative analysis, and five of them were chosen for a meta-analysis. The meta-analysis revealed that photofunctionalization significantly improved the stability of the implant 2 months after implantation (p = 0.04; MD = 3.48; 95% CI = −0.23 to 6.73) and increased the osseointegration speed index (OSI) (p = 0.007; MD = 2.13; 95% CI = 0.57 to 3.68). However, no significant improvements of implant stability were observed 2 weeks (p = 0.62), 4 weeks (p = 0.31), nor 4 months (p = 0.24) after implantation. The evaluation presented no significant reductions in MBL. Conclusions: Based on the positive effect of photofunctionalization on the rate of establishing implant stability, photofunctionalization may provide an effective and practical strategy to achieve faster osseointegration and reduce the overall healing time. Photofunctionalization appears to improve the implant stability. However, the clinical effect of photofunctionalization on MBL remains unclear due to the shortage of available studies. [ABSTRACT FROM AUTHOR]

Nutrient patterns can significantly influence the growth and development of fruit trees, especially fruit quality. In order to clarify the appropriate ratio of inorganic and organic fertilizers, six treatments with different ratios of cow manure and chemical fertilizers were set up in this study to evaluate the effects of different treatments on fruit yield, appearance quality, intrinsic quality and volatile substances. The results showed that, after replacing some chemical fertilizers with cow manure, the content of sugar, titratable acid, organic acid and aroma substance in the fruit increased, the fruit yield and colour did not change significantly, and the fruit weight per fruit decreased. Among the treatments of cow manure with chemical fertilizer, the fruits of 50% chemical fertilizer with 50% cow manure treatment had higher titratable acid (0.4%), malic acid (4.15 mg/g), sorbitol (0.51%), glucose (1.30%), fructose (5.81%) content and total aroma substance content (1047.82 μg/g) than chemical fertilizer alone. Compared to the fertilizer treatment alone, the application of cow manure instead of 50% of the chemical fertilizer had a positive effect on fruit quality. [ABSTRACT FROM AUTHOR]

Experiments of high-throughput electrical discharge milling (HTED milling) of WC-8%Co at 600-A peak current and 4766 mm/min material removal rate (MRR) using a 12-mm-external-diameter and 4-mm-internal-diameter tubular graphite electrode were conducted. The HTED milling process parameters, including peak current, electrode rotation speed, flushing pressure, and peak voltage, were studied to evaluate the effect on MRR, relative electrode wear rate, and diameter of overcut. The cross section, surface morphology, and microhardness of WC-8%Co for HTED milling were also investigated. Peak current has proven to be a critical factor for MRR. The MRR of HTED milling at peak current 600 A can be increased by ten times compared to that of HTED milling at peak current 100 A. Faster electrode rotation speed, larger flushing pressure, and higher peak voltage are essential to achieve low relative electrode wear rate (REWR) and high MRR. This study demonstrates that, using proper HTED milling process parameters and tubular graphite electrode, the HTED milling of WC-8%Co can be processed efficiently. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) was developed over 70 years ago, but the knowledge of plasma channels that form during this process remain understudied. Therefore, this study systematically investigated the breakdown process and impedance characteristics of plasma channels through singe-pulse discharge experiments. The influence of discharge current and gap distance on the breakdown process and impedance characteristics of plasma channels was also analyzed. The results of this work can contribute to the existing body of knowledge of the physical nature of EDM. [ABSTRACT FROM AUTHOR]

To better understand long-term precipitation changes in arid Central Asia, reconstruction of past precipitation is critical. This paper analyzed the core sediments of Balikun lake in eastern Xinjiang. We analyzed 200 pollen samples, combined with 441 surface pollen samples and a radiocarbon chronology, using the Weighted Averaging Partial Least Sequence (WA-PLS) method, to characterize the Holocene high-resolution precipitation change process in Balikun basin. And, Combined with the vegetation types reconstructed by biome method, we discussed the landscape evolution of Balikun basin. Results show that the mean annual precipitation during the Holocene can be broken into three phases: Early Holocene (11,750–8030 cal yr B.P.), which averaged about 130 mm; Middle Holocene (8030–4420 cal yr B.P.), which averaged about 250 mm; and Late Holocene (4420–0 cal yr B.P.), which averaged about 210 mm. The vegetation changed from desert to steppe during the Holocene, and the wetlands gradually expanded, which was mainly informed by precipitation and glacial melt water. [ABSTRACT FROM AUTHOR]

The breakup process of the inviscid liquid bridge sandwiched between two coaxial and equal-sized rods is investigated by tracking its profile. Here, the focus is on the quasi-static profile of the liquid bridge close to rupture and its influence on the subsequent dynamic breakup behaviors. With the increasing distance between the two rods, the profile of the liquid bridge close to rupture undergoes a transition from symmetry to asymmetry. We found there exists a critical slenderness above which the liquid bridge will be asymmetric and present a profile that can be well fitted by one cycle of the sine wave. It is demonstrated both experimentally and theoretically that the ratio of the length of the bridge to its equivalent radius, defined as geometric mean of the radii at the peak and trough of the bridge, is always 2 π for the asymmetric bridge close to rupture. Different with the symmetric evolution of the short bridge, the long asymmetric bridge pinches off first from the side near the bigger sessile drop and then from the other side, which endows the satellite droplet with a lateral momentum, resulting in the satellite re-collected by the sessile drop. The influence of the slenderness on the time interval among the asymmetric pinch-off, velocity, destination, and size of the satellite was investigated. A scaling law was proposed to describe the relationship between the lateral momentum of the satellite and the time interval between two pinch-off. This work is expected to benefit the utilizing or suppressing the satellite in practice. [ABSTRACT FROM AUTHOR]

The bouncing motion of aqueous drops between two oppositely charged electrodes has been observed. However, the forward and backward velocities of the drops are nonuniform in some cases because of unknown reasons. In this study, the velocity difference was mainly caused by the distribution of ions that altered the electric field strength between the electrodes. This result yielded accurate control of the drops in the electric field and opened opportunities for industrial applications. [ABSTRACT FROM PUBLISHER]