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Digital holography, recognized for its noncontact nature and high precision in three-dimensional imaging, is effectively employed to measure the morphology of bubbles and droplets. However, in terms of near-wall bubbles and droplets, such as confined bubbles in microfluidic chips, the measurement of the interface morphology of bubbles near the glass surface has not yet been resolved due to the coherent noise resulting from glass surface reflections in microfluidic chips. Accordingly, an off-axis digital holography system was devised by using Linnik interferometry. Measuring the confined bubble interface near the wall within a microfluidic chip and droplet evaporation on solid surfaces was studied. Partially coherent LED sources and reference light modulation techniques were employed in the optical setup to mitigate the coherent noise. Dual exposure and weighted least-squares unwrapping algorithms were introduced to correct phase distortions, enhancing image quality. Imaging two confined CO2bubbles was done near the wall in silicon oil within a porous microfluidic chip, and contact angles of 4.7 and 4.5° were measured. Additionally, the measurement of the three-dimensional morphology of vertically evaporating deionized water droplets on a glass surface was done, due to which calculation of contact angles at various orientations was possible. This work offers a feasible new method for measuring the 3D interface morphology of bubbles and droplets, particularly in microfluidic visualization, addressing current measurement gaps.

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The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole1–4. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from general relativity5. With a baseline of 17 years of observations, there was a shift in the jet’s transverse position, possibly arising from an 8- to 10-year quasi-periodicity3. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years for the variation in the position angle of the jet. We infer that we are seeing a spinning black hole that induces the Lense–Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.

Capacitor films from biaxially oriented polypropylene (BOPP) involve intensive external stress field, resulting in special crystallization and orientation characters. However, it still remains ambiguous on the relationship between crystallized morphology in BOPP bulk film and electric properties. In this work, two stretching modes, simultaneously biaxial stretching and sequentially biaxial stretching, were chosen to adjust film thickness, extended chain crystal content, fibrillar morphology, and orientation texture. Meanwhile, the working rules of these structural issues on electrical insulating properties were inspected. It reveals that extended chain crystals with thermal stability and isotropous fibrillated network favor to improved breakdown strength and lowered dielectric loss. These results offer good understanding on the processing-structure-property relation of polymer film dielectrics.

Extremely low density carbon nanotubes/graphene hybrid aerogels (CNG) are highly potential active materials for fabricating flexible devices, owing to synergistic effects with one (nanotubes) and two (graphene) dimensional characters in a single structure. However, conquering the long-standing dilemma among low electronic conductivity and inferior mechanical properties for CNG remains a challenging task. Here, an ultralight CNG aerogel (1.52 mg cm–3) with prominent electronic conductivity and mechanical resilience is facilely fabricated through a triple roles design of the sodium dodecyl sulfate (SDS), namely anchoring metal ions, dispersing carbon nanotubes, and inducing self-assembly. It is demonstrated that the Ba2+can be effectively anchored into the GO interlayers by coupling it with the SDS to reinforce the intersheet interactions, thereby achieving remarkable improvement in mechanical properties (Young’s moduli up to 18.3 kPa). Density functional theory calculations reveal that the anchored Ba2+acting as molecular bridges can availably reduce the tunneling barrier between the GO sheets and facilitate the multidirectional and fast transport of electronics, inducing the high electrical conductivity of CNG (12.55 S cm–1). Taking advantage of these features, potential applications in flexible sensing devices have been demonstrated utilizing the remarkable CNG as an active material, giving extraordinary sensing performance including high sensitivity (48.6 kPa–1), ultralow detection limit (10 Pa), and ultrafast response (18 ms).

The electrochemical properties of the metal–organic framework (MOF)-based composite as electrode material can be significantly improved by means of partial destruction of the full coordination of linkers to metal ions and replacing with other small ions, which make metal centers become more accostable and consequently more effective for the lithiation/delithiation process. In this paper, F–was chosen to replace some of the benzenedicarboxylate (BDC) linkers because of its better interaction with the Li+than the oxide ion. What’s more, the formed M–F bond promotes the Li+to transfer at the active material interface and protects the surface from HF attacking. The as-synthesized F-doped Mn-MOF electrode maintains a reversible capacity of 927 mA h g–1with capacity retention of 78.5% after 100 cycles at 100 mA g–1and also exhibits a high discharge capacity of 716 mA h g–1at 300 mA g–1and 620 mA h g–1at 500 mA g–1after 500 cycles. Even at 1000 mA g–1, the electrode still maintains a high reversible capacity of 494 mA h g–1after 500 cycles as well as a Coulombic efficiency of nearly 100%, which is drastically increased compared with pure Mn-MOF material as expected.

Rotary kiln is widely used for thermal disposal of solid waste due to its effectiveness and high efficiency in recent years. To further improve the processing efficiency, a newly designed rotary kiln with three-section structure is proposed, and the behaviours of particle motion and heat transfer are investigated. Firstly, a lab-scale rotary kiln is manufactured, and experiments are carried out. Verified by experimental data, a CFD-DEM numerical model is developed to analyze the particle motion and heat transfer characteristics with the effects of inlet flue gas temperature, feeding rate and rotating speed. The results show that the outlet temperature increases linearly with the flue gas temperature, while it is negatively correlated with the feeding rate and rotating speed. In addition, the volumetric heat transfer coefficient in this complex rotary kiln is analyzed, the overall heat transfer coefficient is between 200 and 700 W/(m3K).

Taking advantage of the condensation between Si–OH of the hydroxylated octadecyltrichlorosilane (OTS) and C–OH on graphene oxide (GO) surface, we grafted OTS onto the GO-based dual-layer film, which was composed of GO outerlayer and (3-aminopropyl)triethoxysilane (APTES) self-assembled underlayer, on a Si substrate. Thus, a hydrophobic trilayer film coded as APTES-GO-OTS was prepared successfully. To confirm the chemical composition, structure, and morphology of the trilayer film, various means including water contact angle measurement, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrometry, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) were performed. Moreover, to investigate the tribological performances, the micro- and macrotribological experiments were conducted with AFM and a UMT tribometer. The results showed that the as-prepared trilayer film exhibited low adhesion and greatly reduced the friction force in both the micro- and macroscale. Therefore, such a trilayer film is suitable for an application in the lubrication and protection of nano/microelectromechanical systems (NEMS/MEMS).

Diatomite (DM) has superior adsorption performance for heavy metal ions in wastewater. However, the application of DM as a demulsifier in the treatment of a crude oil-in-water (O/W) emulsion has not yet been reported in the literature. In this work, a novel amphipathic and magnetically recyclable DM (M-DM) was synthesized by compounding with Fe3O4nanoparticles and surface modifications. M-DM presented favorable demulsification performance under broad pH levels of the crude O/W emulsion. The demulsification efficiency (DE) reached a maximum when the M-DM dosage was increased to 450 mg/L. Moreover, M-DM could be recovered using its magnetism and still retained superior DE for 4 cycles. As a result of the strong interfacial activity, M-DM can reach the oil–water interface and interact with interfacial films. It was believed that the synergistic effect of electrostatic attraction and hydrogen bond interaction between M-DM and asphaltenes (main component of the interfacial film) promoted the rupture of the interfacial film and accelerated the coalescence of oil droplets to realize the oil–water separation of the O/W emulsion. This work provides a prospective novel demulsifier with cost-efficient, environmentally friendly, and universal application for the treatment of crude O/W emulsions.

Inorganic halide perovskite CsPbI2Br has attracted tremendous attentions in the photovoltaic fields in view of its improved ambient phase stability and reasonable band gap (1.91eV). Traditional one-step solution-processed CsPbI2Br absorbers, however, usually suffer from poor morphology, low crystallinity and thin thickness, which impede further promotion of device performance. Herein, an anti-solvent assisted multi-step deposition strategy for high-quality CsPbI2Br film is demonstrated, wherein different anti-solvents are first introduced in the PbI2precursor filming processes to construct porous PbI2(DMSO) films. Then CsBr solution intercalates into the porous PbI2(DMSO) film by multi-step deposition, effectively facilitating the close contact of reactants and complete annealing reaction. CsBr drops and porosity degree of PbI2(DMSO) film are found to control the final morphology and phase composition of the perovskite film. Utilizing green ethanol (EtOH) treated PbI2film with high porosity and randomized orientation, highly pure-phase and full-coverage CsPbI2Br films with high thickness, large grain sizes and high crystallinity are obtained after optimizing CsBr drops. Finally, carbon-based all-inorganic planar perovskite solar cells (PSCs) with absorbers prepared through above methods achieve a champion efficiency of 10.21%, which is a record value for the CsPbI2Br PSCs without hole transport layer. More importantly, the unencapsulated all-inorganic CsPbI2Br device shows a promising long-term stability with no obvious efficiency degradation when exposed in ambient atmosphere with 15–30% relative humidity (RH) at room temperature for 44 days.

Three-dimensional graphene (3DG) aerogels possessing superior elasticity and conductivity are prerequisite to achieve high sensitivity and reliability in flexible sensors. However, conventional 3DG aerogels with brittle structure and small recoverable deformation often do not possess excellent sensing performance. Herein, 3DG–poly(vinyl alcohol) (3DG–PVA) composite aerogels with controlled structures and properties are designed and prepared by PVA-mediated self-assembly of graphene oxide nanosheets combining the hydrothermal reaction and freeze-drying processes. The resulting aerogels exhibit robust structure with high porosity, superior elastic deformation, decent electrical conductivity, and outstanding electromechanical performances including a high sensitivity of 0.34 kPa–1, a fast response time of 63.9 ms, and an excellent signal stability of over 5000 times of cycling. To demonstrate their potential applications in the field of piezoresistive sensing, the wearable sensors are designed and fabricated by using 3DG–PVA aerogels, which exhibit the anisotropic sensing capabilities and ultrasensitive performances confirmed by practical applications in monitoring the motions of human joints with different orientations, as the sensing part.

Polymeric elastomers integrated with high mechanical toughness and excellent self-healing ability can find attractive applications in electronic skin, soft robotics, and electrical devices. However, simultaneously enhancing the mechanical and self-healing properties of elastomers is still a great challenge because it is difficult to balance the effects between strong and weak cross-linking bonds. Here, a novel self-healing elastomer is developed via a one-pot polycondensation reaction between bis(3-aminopropyl)-terminated poly(dimethylsiloxane) and 2,4′-tolylene diisocyanate, followed by being coordinated with Al(III) ions by metal-coordination bonds. In this elastomer system, the quadruple hydrogen bonds not only are able to achieve rapid reformation after fracture but also can dissipate strain energy as a weak dynamic bond, endowing the elastomer with excellent self-healing ability and high stretchability, while the treble Al-coordination bonds acting as a strong dynamic bond contribute to the robust molecular networks, leading to the significantly improved robustness and elasticity of the self-healing elastomer. Owing to the accuracy design, the synthesized elastomer exhibits all the desired properties, including high tensile stress (2.6 MPa), exceptional toughness (∼14.7 MJ m–3), high stretchability (∼1700%), and excellent self-healing ability (90%). The robust self-healing elastomer enables the easy fabrication of flexible electronic skin, which will open a new avenue for next-generation electrical devices.

Three-dimensional graphene oxide–carbon nanotube (GO–CNT, abbreviated as GCNT) aerogels can find wide applications in various fields. Especially, low-density GCNT aerogels featuring both high conductivity and superelasticity are essential requirements for the construction of highly sensitive pressure sensor. However, simultaneous improvement on the electrical and mechanical properties of low-density GCNT is still a great challenge owing to their disordered microstructure, severe structural defects and massive oxygen-containing functional groups. Here, a structurally ordered and less defective GCNT aerogel featuring both high conductivity and superelasticity has been fabricated through alkali induced self-assembly of GO liquid crystals (GO LCs) and CNTs. Our methodology relies on the double roles of KOH solution as dispersant for CNTs and an inducer for the self-assembly of GO LCs nanosheets. The less-defective CNTs acting as reinforcement material contributes to the robust structure networks, leading to the significantly improved conductivity (2.4 S m–1) and elasticity (14.3 kPa) of GCNT. Benefiting from these outstanding properties of GCNT aerogels, the assembled pressure sensor exhibits an ultrahigh sensitivity of 1.22 kPa–1, rapid response time of 28 ms and excellent cycling stability, which enables it as a high-performance sensing platform to monitor various human motions in real time.

The bulk materials of three-dimensional graphene (3DG) with high network structure and excellent electrical conductivity have many potential applications in flexible electronics, but the network structure is not very stable due to weak bonding between graphene nanosheets. Here, a polyimide (PI) layer was introduced on the as-prepared 3DG sponge by vacuum infiltration–curing method. The resulting 3DG/PI composite sponges with robust 3D network structure exhibited an excellent electrical conductivity (3.7 S/cm), compression strength (175 kPa), elasticity, and flexibility, as well as outstanding compression sensitivity to resistance and stable piezoresistance effect; namely, they possess a large change in resistance in response to application of small strain and low density, and the resistance change remains favorably stable after performing 300 compress–release cycles, which means that the prepared composite sponges can find wide applications in pressure-sensing or stimulus-responsive graphene system.

MXenes are an emerging class of new two-dimensional materials, which have been widely used in energy storage, catalysis, sensing, biology, and other fields due to their unique structure and properties. The distinct structure, low shear resistance, and easy-to-modify ability endow MXenes with particularly superior lubrication potentials. This review highlights the research status and applications of MXenes lubrication categorized into solid lubricants, lubricant additives, and reinforcement phase parts, summaries the influencing factors and lubrication mechanisms of MXenes lubrication, points out some unexplored research fields and unsettled questions, and then puts forwards possible solutions and prospects for the future research. The lubrication advances and potentials of MXenes are fully verified. Predictably, the emerging MXenes lubricants will exhibit remarkable application prospects in advanced manufacturing such as machining industries, automotive industries, micro/nano-electromechanical systems, and spacecraft components.

Porous electrodes with high specific surface areas have been commonly employed for alkaline water electrolysis. The gas bubbles generated in electrodes due to water electrolysis, however, can screen the reaction sites and hinder reactant transport, thereby deteriorating the performance of electrodes. Hence, an in-depth understanding of the behavior of bubbles in porous electrodes is of great importance. Nevertheless, since porous electrodes are opaque, direct observation of bubbles therein is still a challenge. In this work, we have successfully captured the behavior of bubbles in the pores at the side surfaces of nickel-based porous electrodes. Two types of porous electrodes are employed: the ones with straight pores along the gravitational direction and the ones with tortuous pores. In the porous electrodes with tortuous pores, the moving bubbles are prone to collide with the solid matrix, thereby leading to the accumulation of bubbles in the pores and hence bubble trapping. By contrast, in the porous electrodes with straight pores, bubbles are seldom trapped; and when two bubbles near the wall surfaces coalesce, the merged bubble can jump away from the wall surfaces, releasing more active surfaces for reaction. As a result, the porous electrodes with straight pores, although with lower specific surface areas, are superior to those with tortuous pores. The relationship among the pore structures of porous electrodes, bubble behavior, and electrode performance disclosed in this work provides deep insights into the design of porous electrodes.

Although the fluorinated graphene (FG) possesses numerous excellent properties, it can not be really applied in aqueous environments due to its high hydrophobicity. Therefore, how to achieve hydrophilic FG is a challenge. Here, a method of solvent-free urea melt synthesis is developed to prepare the hydrophilic urea-modified FG (UFG). Some characterizations via transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transfer infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermo gravimetric analysis (TGA) demonstrate that the urea molecules can covalently functionalize the FG and the hydrophilic UFG can be prepared. According to the tribological tests run on an optimal-SRV-I reciprocation friction tester, it can be found that the antiwear ability of water can be largely improved by adding the appropriate UFG. When the concentration of UFG aqueous dispersion is 1 mg/mL, the sample of UFG-1 has the best antiwear ability with a 64.4% decrease of wear rate compared with that of the pure water (UFG-0), demonstrating the prepared UFG can be used as a novel and effective water-based lubricant additive.

Enzymatic loss and inactivation are two main problems that can degrade the performance of biosensor. In order to resolve the problems, a new enzymatic immobilization carrier was developed by using biomimetic methods. Horseradish peroxidase (HRP) was initially encapsulated into zeolitic imidazolate frameworks (ZIFs) severed as protective structure. To overcome electron transfer barrier of ZIFs, graphene oxide (GO) of high conductive graphene precursor was used to enhance their conductivity. Subsequently, ZIFs@HRP/GO and GO-polyethyleneimine with opposite charges were alternatively assembled onto the substrate of indium tin oxide to construct multilayer films of the biosensor. Systematic characterizations showed that ZIF-8 with an average size of approximately 160.9 nm encapsulating HRP uniformly grew onto the surface of GO. The newly designed structure combined with the excellent properties of the GO and ZIFs guarantee easy, direct electrochemistry and good catalytic activity toward H2O2 oxidation can be achieved with this biosensor. Electrochemical experiment study indicate that the resulting biosensor presented a wide linear range of 0.02-6 mmol/L, a low detection limit of 3.4 umol /L (S/N = 3), excellent anti-interference ability, and long-term stability as well.

This study reports a simple synthesis of amorphous nickel tungstate (NiWO4) nanostructure and its application as a novel cathode material for supercapacitors. The effect of reaction temperature on the electrochemical properties of the NiWO4electrode was studied, and results demonstrate that the material synthesized at 70 °C (NiW-70) has shown the highest specific capacitance of 586.2 F g–1at 0.5 A g–1in a three-electrode system. To achieve a high energy density, a NiW-70//activated carbon asymmetric supercapacitor is successfully assembled by use of NiW-70 and activated carbon as the cathode and anode, respectively, and then, its electrochemical performance is characterized by cyclic voltammetry and galvanostatic charge–discharge measurements. The results show that the assembled asymmetric supercapacitor can be cycled reversibly between 0 and 1.6 V with a high specific capacitance of 71.1 F g–1at 0.25 A g–1, which can deliver a maximum energy density of 25.3 Wh kg–1at a power density of 200 W kg–1. Furthermore, this asymmetric supercapacitor also presented an excellent, long cycle life along with 91.4% specific capacitance being retained after 5000 consecutive times of cycling.

Casein phosphopeptides (CPPs) with abundant phosphoserine clusters can mediate hydroxyapatite (HA) nucleation and growth. In this work, a new type of CPPs-biofuctionalized graphene composite was synthesized by amidation reaction between CPPs and carboxyalated graphene (CGO). When immersed in stimulated body fluid (1.5 × SBF) at 37 °C for different periods, the CPPs layer on the composite facilitated efficient interaction between the CGO surface and mineral ions, which promoted HA nanoparticle formation and shortened mineralization time in comparison with pristine CGO. The synthesis of the composite mimicked the natural biomineralization of bone, demonstrating that CPPs can effectively improve the bioactivity of graphene and be useful for HA formation. The presented biocomposite may have potential biomedical applications in different areas.

A novel 3-layer organic film was fabricated on silicon wafer with a polydopamine coating (coded as PDAc) as the interlayer by a multistep self-assembly process. The formation and structure of the films were analyzed by means of ellipsometric thickness measurement, water contact angle measurement, and attenuated total reflection-Fourier transform infrared spectrometry (ATR-FTIR). Meanwhile, an atomic force microscope (AFM) characterization was performed to evaluate the adhesive and microtribological behaviors of the 3-layer film, and a ball-on-plate tribometer was used to test macrotribological performance. As results show, the as-prepared 3-layer film possessed the excellent tribological properties characterized by lower friction and higher antiwear ability, which was ascribed to the special chemical structure of the film, i.e., the strong adhesion of the film to the silicon wafer, the chemical bonding between the adjacent layers, the cross-linked structure of the PDAc interlayer, and the hydrophobicity, high flexibility, and high elasticity of the stearoyl chloride (STC) outer layer. Hopefully, the present work provides a feasible route to construct a multilayer film with excellent structural stability and tribological behavior. The titled multilayer film might find potential applications in boundary lubrication and many other areas.

Sensing materials that are ultrastrong but still superelastic and highly sensitive are crucial for meeting the requirements of future flexible sensors. However, these requirements are challenging to satisfy simultaneously due to the internal constraints among these properties. Here, an ultrastrong and superelastic eutectogel is designed and prepared using a waterborne polyurethane (WPU) network enhanced by two-dimensional (2D) nanosheets in a deep eutectic solvent. The 2D nanosheet-induced noncovalent cross-linking endows the prepared eutectogel with superelasticity and flexibility, and its elongation at break reaches 2071%, higher than those of most polymers (<1000%). Meanwhile, this eutectogel also exhibits a high tensile strength (21.6 MPa), which is strong enough to support 20 000 times its own weight. Such a composite design provides a feasible route for preparing eutectogels with outstanding comprehensive functions without trade-offs among these features. In addition, the eutectogel-assembled sensor possesses a high ionic conductivity of 0.225 S/m and a high strain sensitivity of 1.18 kPa–1. Furthermore, it can be integrated into the sensing arrays for multidimensional signal monitoring without diminishing its pristine strength and flexibility. Surprisingly, the eutectogel can be quickly disintegrated in ethanol due to the WPU’s pseudoplastic behavior, providing a competitive way to dispose of waste electronic devices.

The Zr and Co co-doped LiMn2O4nanowires are fabricated successfully by using sol–gel process with porous anodic aluminum oxide (AAO) as the template. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization show that the synthesized LiZrxCoyMn(2-x-y)O4nanowires are uniformly distributed, high-ordered, and parallel to each other, and few microscopic defects are found. Selected area electron diffraction (SAED) pattern, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) investigations jointly demonstrate that the synthesized nanowires have a similar single spinel structure of LiMn2O4crystal though Zr and Co are doped. Since the LiZrxCoyMn(2-x-y)O4nanowires can be mass-produced by using this method, it is expected to find promising application as a new cathode material in lithium ion battery.The Zr and Co co-doped LiMn2O4nanowires are fabricated successfully by using sol–gel process with porous anodic aluminum oxide (AAO) as the template. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization show that the synthesized LiZrxCoyMn(2-x-y)O4nanowires are uniformly distributed, high-ordered, and parallel to each other, and few microscopic defects are found. Selected area electron diffraction (SAED) pattern, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) investigations jointly demonstrate that the synthesized nanowires have a similar single spinel structure of LiMn2O4crystal though Zr and Co are doped. Since the LiZrxCoyMn(2-x-y)O4nanowires can be mass-produced by using this method, it is expected to find promising application as a new cathode material in lithium ion battery.

A peptide-containing alkylsilane self-assembled monolayer on silicon surface has been prepared successfully by a simple one-step strategy. The formation and structure of the peptide-containing SAMs were characterized by means of contact angle measurement, ellipsometry, FT-IR, and AFM morphology observation. It was found that the water content in the hydrolysis solution plays a key role in determining the quality of the monolayers. The micro-tribological properties of various films were evaluated by using AFM, while the macro-tribological study was performed on a ball-on-plate tribometer. It was found that the peptide-containing monolayers possess excellent friction-reduction and antiwear ability, which was attributed to its amide-containing structure. In other words, the interchain hydrogen bonds among the molecules enhance the stability of the monolayers against rubbing the counterpart ball and thus endow it an outstanding antiwear ability.

In the yeast Saccharomyces cerevisiae, ultradian oscillations of energy metabolism have been observed in continuous cultures. Here, we found that the level of the GTS1gene product oscillated in concert with the ultradian rhythm of energy metabolism. When GTS1was inactivated by gene disruption, the metabolic oscillation was affected severely, mostly disappearing within a day, in the absence of synchronized stress‐response oscillations throughout the continuous culture. The disappearance of biological rhythms in the GTS1‐deleted mutant was substantially rescued by transformation with chimera plasmids carrying GTS1under the control of GTS1's own promoter. On the other hand, this disappearance was not rescued by constitutive expression of GTS1under the control of the triose phosphate isomerase promoter.

In the yeast Saccharomyces cerevisiae, ultradian oscillations of energy metabolism have been observed in continuous cultures. Here, we found that the level of the GTS1gene product oscillated in concert with the ultradian rhythm of energy metabolism. When GTS1was inactivated by gene disruption, the metabolic oscillation was affected severely, mostly disappearing within a day, in the absence of synchronized stress-response oscillations throughout the continuous culture. The disappearance of biological rhythms in the GTS1-deleted mutant was substantially rescued by transformation with chimera plasmids carrying GTS1under the control of GTS1’s own promoter. On the other hand, this disappearance was not rescued by constitutive expression of GTS1under the control of the triose phosphate isomerase promoter.

We investigated whether cellular responses to various stress conditions are regulated in synchronization with the ultradian rhythm of respiratory–fermentative metabolism which is coupled to the cell cycle rhythm in continuous cultures of the yeast Saccharomyces cerevisiae. The cellular resistance to heat oscillated with a peak at the late respiro–fermentative phase, which approximately corresponds to the unbudding period of the cell cycle. Cellular resistance to H2O2and that to the superoxide‐generating agent menadione oscillated in the same phase as that of heat resistance. The resistance to cadmium and that to 1‐chloro‐2,4‐dinitrobenzene, an uncoupler of energy metabolism in mitochondria, both oscillated with a peak advanced by about 80° relative to that of heat resistance, approximately covering the respiro–fermentative phase. Thus, cellular resistance to various stresses in S. cerevisiaeoscillated in synchronization with the metabolic oscillation in the continuous culture.

We tested the effect of theGTS1gene of the yeastSaccharomyces cerevisiaeon the cyanide-induced ultradian oscillation of the glycolytic metabolite NADH in cell suspension of strains with different copy numbers of the gene, that is, the wild-type,GTS1-disrupted andGTS1-overexpressing strains. The cells showed long-lasting oscillations when harvested between 1 and 2 hours after the diauxic shift from glucose to ethanol as a growth substrate. The frequencies of oscillation did not vary very much among the three strains tested. However, the amplitudes and durations of the oscillation were changed significantly as a function of theGTS1gene-dosage. The effect of GTS1 on the amplitude was not caused by changing rates of glucose incorporation into cells as the rates were the same among the three strains during the macroscopic oscillation.

In the present work, an amphiphilic and magnetically recyclable graphene oxide (MR-GO) demulsifier was devised and synthesized by graft of magnetic nanoparticles (Fe3O4@SiO2-APTES) and ethylenediamine on the GO surface. The wettability and surface charges of MR-GO under various pH conditions can be regulated via adjusting the contents and species of surface functional groups (such as amino, carboxyl, and hydroxyl). In the demulsificaition test, MR-GO displayed favorable demulsification performance for crude oil-in-water (O/W) emulsion under pH of 2.0–10.0, thusly greatly improving the application scope of common demulsifier. The optimal dosage of MR-GO was 200 mg/L and the demulsification efficiency attained a maximum value of 99.7% for crude O/W emulsion with pH of 6.0. What’s more, owing to its magnetic response performance, the MR-GO can be reused and the demulsification efficiency remained above 91.0% after six cycles. Based on the strong interfacial activity, MR-GO can arrive to the crude oil–water interface. With the synergy effects of interfacial adsorption (π–π/n−π) interactions and electrostatic attraction of demulsifier and interfacial films, and the aid of external mechanical forces, the interfacial films stabilized the emulsion were disrupted. Therefore, the oil droplets coated on the water droplets were gathered rapidly to form oily flocs and then migrated to the water surface to accomplish the demulsification of crude O/W emulsion.

Enzymatic loss and inactivation are two main problems that can degrade the performance of biosensor. In order to resolve the problems, a new enzymatic immobilization carrier was developed by using biomimetic methods. Horseradish peroxidase (HRP) was initially encapsulated into zeolitic imidazolate frameworks (ZIFs) severed as protective structure. To overcome electron transfer barrier of ZIFs, graphene oxide (GO) of high conductive graphene precursor was used to enhance their conductivity. Subsequently, ZIFs@HRP/GO and GO-polyethyleneimine with opposite charges were alternatively assembled onto the substrate of indium tin oxide to construct multilayer films of the biosensor. Systematic characterizations showed that ZIF-8 with an average size of approximately 160.9 nm encapsulating HRP uniformly grew onto the surface of GO. The newly designed structure combined with the excellent properties of the GO and ZIFs guarantee easy, direct electrochemistry and good catalytic activity toward H2O2oxidation can be achieved with this biosensor. Electrochemical experiment study indicate that the resulting biosensor presented a wide linear range of 0.02–6 mmol/L, a low detection limit of 3.4 μmol /L (S/N = 3), excellent anti-interference ability, and long-term stability as well.

We investigated whether cellular responses to various stress conditions are regulated in synchronization with the ultradian rhythm of respiratory–fermentative metabolism which is coupled to the cell cycle rhythm in continuous cultures of the yeast Saccharomyces cerevisiae. The cellular resistance to heat oscillated with a peak at the late respiro–fermentative phase, which approximately corresponds to the unbudding period of the cell cycle. Cellular resistance to H2O2 and that to the superoxide-generating agent menadione oscillated in the same phase as that of heat resistance. The resistance to cadmium and that to 1-chloro-2,4-dinitrobenzene, an uncoupler of energy metabolism in mitochondria, both oscillated with a peak advanced by about 80° relative to that of heat resistance, approximately covering the respiro–fermentative phase. Thus, cellular resistance to various stresses in S. cerevisiae oscillated in synchronization with the metabolic oscillation in the continuous culture.