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Poly(ethylene glycol) (PEG) is widely utilized as a hydrophilic coating to extend the circulation time and improve the tumor accumulation of polymeric micelles. Nonetheless, PEGylated micelles often activate complement proteins, leading to accelerated blood clearance and negatively impacting drug efficacy and safety. Here, we have crafted amphiphilic block copolymers that merge hydrophilic sulfoxide-containing polymers (psulfoxides) with the hydrophobic drug 7-ethyl-10-hydroxylcamptothecin (SN38) into drug-conjugate micelles. Our findings show that the specific variant, PMSEA-PSN38 micelles, remarkably reduce protein fouling, prolong blood circulation, and improve intratumoral accumulation, culminating in significantly increased anti-cancer efficacy compared with PEG-PSN38 counterpart. Additionally, PMSEA-PSN38 micelles effectively inhibit complement activation, mitigate leukocyte uptake, and attenuate hyperactivation of inflammatory cells, diminishing their ability to stimulate tumor metastasis and cause inflammation. As a result, PMSEA-PSN38 micelles show exceptional promise in the realm of anti-metastasis and significantly abate SN38-induced intestinal toxicity. This study underscores the promising role of psulfoxides as viable PEG substitutes in the design of polymeric micelles for efficacious anti-cancer drug delivery. This study emphasizes PMSEA's potential as a sulfoxide-containing polymer for anti-cancer drug delivery, offering an alternative to PEG in constructing polymeric prodrug micelles efficiently. [Display omitted] • Sulfoxide-containing polymer PMeSEA presents a promising alternative to PEG. • Micelles grafted with PMeSEA successfully diminish complement system activation. • Reducing complement activation enhances the antitumor activity of PMeSEA-micelles. [ABSTRACT FROM AUTHOR]

The bubble dynamic behaviors on the electrode surface are significantly affected by the magnetohydrodynamic (MHD) flow induced by the Lorentz force resulting from the applied magnetic field. However, the mechanism of the impact of a magnetic field perpendicular to the electrode on the dynamic behaviors of bubble remain unclear. In this study, the evolution law of a single oxygen bubble on the surface of a TiO2 photoelectrode under the influence of a vertical magnetic field with different magnetic induction intensities was investigated. The presence of a vertical magnetic field effectively promoted the rapid detachment of bubbles from the electrode surface and greatly improved the gas evolution efficiency. The mass transfer was dominated by single-phase free convection during bubble evolution. Under the influence of the vertical magnetic field, the mass transfer coefficient near the electrode was enhanced, and the adverse effects of bubbles on mass transfer were counteracted when they entered the reaction-controlled growth phase. The further multiphysics simulation found that the MHD convection decreased the local supersaturation of reaction product oxygen molecules near the electrode, thereby reducing concentration overpotential and increasing the reaction rate. This study provides an experimental and theoretical basis for promoting the bubble detachment and the reaction rate on the gas evolving electrode surface during photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]

The liquid carry-over (LCO) phenomenon brings about the performance deterioration of gas–liquid cyclone separator and an increase in pressure drop. However, the formation mechanism of the LCO and its manifestation in the separator cylinder and the overflow pipe have not been fully understood. This work investigated the flow process of the LCO by visual observation and quantitative measurement of the overflow liquid flow rate and liquid holdup. The transient gas–liquid flow feature in the overflow pipe and spatiotemporal relationship between the separator inlet and outlet were characterized by time-frequency analysis and wavelet coherence of liquid holdup, respectively. The results showed that the size of air core determines two kinds of sources of the LCO, including the surrounding liquid direct entry into the overflow pipe and the film short-circuit flow beneath the top wall of the separator. When the air core can continuously wrap up the overflow inlet, the film short-circuit flow became the primary source of the LCO, which was embodied in the significant reduction of the overflow liquid flow rate. Three flow patterns, namely, slug flow, churn flow, and annular flow, were classified in the overflow pipe. The inlet intermittent flow of the separator led to the distribution of churn flow expanding toward higher gas velocity, which was interpreted by flow pattern transition theory. The time-averaged overflow liquid holdup was well predicted by drift-flux model. The results are beneficial to the proposal of inhibition methods of the LCO and structure design of the separator. [ABSTRACT FROM AUTHOR]

• A novel combined separator was designed and investigated. • Novel separator can effectively broaden operating conditions of efficient separation. • The pressure drop of the novel separator is significantly reduced by more than 50%. • Prediction method for pressure drop is proposed based on the separated flow model. The cyclone separator is widely used as the efficient steam separation device for the nuclear reactor. In this study, a novel gas–liquid separator that can realize efficient and stable gas–liquid separation under a wide range of working conditions is designed. The separator is organically combined with an axial cyclone separator and a tangential cyclone separator. The axial cyclone separator performs the role of rectification and pre-separation, and the tangential cyclone separator ensures separation performance. The variation in the gas–liquid interface characteristics and separation characteristics of cyclone separation under different inlet flow rates are investigated. Compared with the single tangential cyclone separator, the separation deterioration range of the novel separator is significantly reduced. The addition of the pre-separator effectively broadens the operating conditions for efficient separation. The pressure drop of the novel separator is reduced by more than 50 %. Based on the separated flow model, the relationship between the separation pressure drop ratio and dimensionless number is established, and the prediction method for the pressure drop is put forward with the prediction accuracy within ±10 %, which provides reference for the practical application of the novel separator. [ABSTRACT FROM AUTHOR]

One falling liquid droplet impacting a sessile droplet and then undergoing oscillation is a common phenomenon in both nature and industry. However, to the best of our knowledge, the head-on collision of two nanofluid drops has not been studied when both the nanoparticle and surfactant exist in the drop. In this work, the characteristics of oscillation after head-on collision of two TiO2-water nanofluid drops were investigated experimentally. The effects of impact velocity, drop size, and nanoparticle concentration have been considered to understand how they influence the drop spreading, recoiling, and rebounding. For the influence of the drop size, it shows that in 0% and 0.001% of nanoparticle concentrations, the relative spreading radius of small drop size is higher than that with large size, while it is reversed in 0.01% and 0.1% of nanoparticle mass fractions. Interestingly, it was found that there is an optimal nanoparticle mass fraction of 0.1% for nanofluid droplets where the oscillation of head-on collision can be damped much more rapidly than that for nanoparticle-free droplets. A hypothesis considering the comprehensive interaction of surfactant redistribution, surfactant gradient, and particle initial effect was proposed to explain the observed phenomenon. This work will be of significant reference to various practical applications especially when the drop collision oscillation characteristics are supposed to be under control. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial cellulose (BC) was used as a raw material to produce freestanding carbon aerogels (CAs). The CAs were further decorated with Ni and MnO2/Ni(OH)2 hybrid via electrodeposition and redox reaction to produce carbon nanofiber networks decorated with electrochemically active metal and metal compounds. The properties of this novel material as supercapacitor electrodes were investigated. The electrochemical performance of the electrodes was examined in 1 M Na2SO4 electrolyte using cyclic voltammetry (CV), cyclic charge-discharge (CCD), and electrochemical impedance spectroscopy (EIS) tests. The results showed that a specific capacitance of 109 F g−1 was achieved at the current density of 1 A g−1. The electrodes could deliver an energy density of 9.4 Wh kg−1 and a power density of 4 KW kg−1 and demonstrated a high cyclability. These results showed great potential of this new material for supercapacitor electrodes. A flexible solid-state supercapacitor prototype was prepared using this material to demonstrate its function as a power source for a LED light. This study provided a new way to use BC as a biobased low-cost material for the fabrication of energy storage devices.Graphical Abstract: [ABSTRACT FROM AUTHOR]

• Separated flow around the perforated tube is studied experimentally. • The void fraction in the wake region is independent of the inlet liquid flow rate. • The flow pattern contributes to the variation of air separation efficiency. • The separation parameters can be predicted using minimum kinetic energy principle. Gas-liquid separator plays an important role in the reactor fission gas removal system. Utilizing the differential pressure formed by flow around the perforated tube, the separator achieves gas–liquid separation, meanwhile having advantages such as simple structure. The evolution characteristics of gas–liquid interface and the variation of parameters such as separation efficiency and pressure drop under plug flow and slug flow are investigated. The void fraction in wake region is only related to the inlet volumetric fraction. The variation of air separation efficiency with inlet volumetric fraction is influenced by the inlet flow pattern, and the separation purity increases with the inlet volumetric fraction. The prediction methods of air separation efficiency, pressure drop and other parameters based on Weber number and liquid phase Reynolds number are obtained in accordance with dimensional analysis and minimum kinetic energy principle with the prediction accuracy within ±20 %, which provides guidance for practical application and optimization. [ABSTRACT FROM AUTHOR]

Although turbulent flow is generally needed for good suspension of photocatalysts, lower flow rates are preferred from an economic viewpoint for energy-efficient operation. However, no experimental work has been conducted to reveal how photocatalyst particles move and distribute in a tubular photocatalytic reactor under mild operating conditions, which is critical for reactor design and configuration of the light concentration. In our study, the photocatalyst itself was employed as a tracer particle for Particle Image Velocity (PIV) measurement. PIV combined with a new laser sheet image analysis (LSIA) technology was employed to investigate both the particle velocity and number distribution in the tubular reactor. It was found that, in the inlet, a higher velocity distribution of fluid generally occurred in the lower part of the tube. However, in the middle and outlet regions of the tube, a higher velocity distribution existed in the upper part of the tube. LSIA investigation showed that the transport capacity of the fluid and the initial particle size distribution are two essential factors influencing particle number distribution in the suspension. Regardless of the particle size, the middle part of the reactor holds the maximum number of particles while the outlet has the minimum number of particles. In the inlet, both small and large particles show similar number distribution trends against the flow rate. However, in the middle part of the tube, the number of small particles decreases with the flow rate while the number of the large particles shows the opposite trend. The difference in velocity distribution along the radial direction also significantly affects the particle distribution. One interesting finding is that, regardless of the particle size, the number of particles in the upper part of the tube is always higher than that in centre. Stokes’ drag law and the Saffman lift force were employed to explain this experimental finding. In the last section, the correlation between particle distribution and optical properties was numerically investigated by a modified differential approximation (MDA) method. [ABSTRACT FROM AUTHOR]

Bubbles evolving from electrode surface are the results of the multi-processes, interfacial mass transfer, chemical reaction, micro fluid flow, etc. In this paper, the investigations on the bubble growth mechanism during photoelectrochemical and electrochemical conversions are carried out. The experimental results show two different growth laws during photoelectrochemical and electrochemical conversions, which are chemical reaction and diffusion controlled respectively, caused by the difference in the effective surface area of the electrode. And mathematical models for bubble growth describing the two effects are established. [ABSTRACT FROM AUTHOR]

Nanofluids as thermal absorption media or optical filters have showed great potential for application in direct absorption solar collector or hybrid photovoltaic/thermal (PV/T) collectors. Due to their nanoscale size and high surface energy, particles in nanofluid have a great tendency to aggregate into large secondary agglomerate, even in the presence of the anti-agglomeration agent, which could in turn lead to significant change in the thermal and optical properties of the nanofluid. However, rare work has been carried out to investigate the relation between the aggregation and optical properties of the nanofluid, which in our view, is of great importance for the enhanced performance of the nanofluid in solar collectors. In this study, taken alumina nanofluids with controlled particle aggregation properties as example, we were able to investigate the underlying correlation between the size distribution of the aggregate in nanofluid and their resulting absorption coefficients. It was found that inhibited aggregation and resultant smaller aggregated particle size could lead to larger absorption coefficient. Both Rayleigh scattering and Mie scattering theories have been attempted to predict the optical properties of the nanofluid after particle aggregation. The results indicate that values obtained by Rayleigh scattering theory are several orders higher than experimental values but that predicted by Mie scattering theory can reasonably match with the experimental results. Specially, it was demonstrated that by introducing the projected areas of the nanoparticle aggregate corresponding to smallest sphere enclosing diameter, more accurate absorption coefficient prediction based on Mie theory can be obtained. Our study is expected to provide a valuable guidance for the regulation of the optical properties of nanofluids and to improve their performance in solar collectors. [ABSTRACT FROM AUTHOR]

Flow accelerated organic coating degradation has been received attention, but the degradation mechanism is still not completely understood. In this study, we focus on investigating the influence of fluid shear on the degradation of organic coatings. A commercially available epoxy based clear coating was exposed to the laminar flow, and a 3.5 wt% NaCl solution was employed as the working fluid with a variety of flow rates. The change in the composition of the working fluid during the coating immersion was characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The effect of fluid shear is also demonstrated by the change in coating thickness. The barrier properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. The time evolution of coating resistance, capacitance, and permittivity obtained from the equivalent circuit model was studied to demonstrate the internal composition change of the coatings due to the flowing fluid. In this study, the experiments and analysis confirmed that flowing fluid promotes the release of coating materials from the coating into the surrounding working fluid while it accelerates the transport of water and ions into the coating. [ABSTRACT FROM AUTHOR]

Malonyl-CoA is the essential building block of natural products such as fatty acids, polyketides, and flavonoids. Engineering the biosynthesis of fatty acids is important for biofuel production while that of polyketides provides precursors of medicines and nutritional supplements. However, microorganisms maintain a small amount of cellular malonyl-CoA, which could limit production of lipid and polyketides under certain conditions. Malonyl-CoA concentration is regulated by multiple pathways and signals, and changes in intracellular malonyl-CoA often lead to complex alterations in metabolism. In the present work, overexpression of a plant malonyl-CoA synthetase gene ( AAE13) in Saccharomyces cerevisiae resulted in 1.6- and 2.4-fold increases in lipid and resveratrol accumulation simultaneously. We also demonstrated that AAE13 partially complemented the temperature-sensitive acc1 mutant, replacing this key enzyme in central metabolism. Mechanistic analysis by CoA quantification and transcriptomic measurement suggested that increases in malonyl-CoA concentration were coupled with drastic reductions in other major CoA compounds and clear suppression of tricarboxylic acid cycle-related genes. These results suggest that malonyl-CoA is a critical target for fatty acid and polyketide engineering and that overexpression of malonyl-CoA synthetic enzymes needs to be combined with upregulation of CoA synthesis to maintain metastasis of central metabolism. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pure water and NaCl solution were used as working fluids for coating degradation. [•] Electrochemical impedance spectroscopy was used to quantify coating degradation. [•] A suitable equivalent circuit model was employed. [•] More water uptake was found in coatings immersed in pure water. [•] Pure water deteriorates more efficiently coating's barrier property. [ABSTRACT FROM AUTHOR]

The motion, deformation, and stability of compound droplets in extensional flows are investigated numerically via a three-dimensional spectral boundary element method. We examine the droplet stability under the influences of the capillary number, the inner droplet size and the relative magnitude of the surface tension of the two interfaces composing the compound droplet. The influence of viscosity on the droplet deformation is also discussed. We conclude that a compound droplet with a larger inner droplet and/or smaller inner surface tension is less stable and cannot withstand strong flow. For moderate viscosity ratios, a compound droplet with a more viscous 'shell' exhibits larger deformation at steady state. In addition, for an eccentric compound droplet, both the inner and outer droplets tend to migrate away from its original location due to the asymmetry of the problem. The initial location of the inner droplet also influences the droplet stability as well as the migration velocity of the compound droplet. [ABSTRACT FROM AUTHOR]

Abstract: Corrosion protective coatings are known to degrade due to moisture exposure. To predict coatings service lifetime, acceleration tests are necessary. We employ flowing deionized water to accelerate coating degradation. Coating barrier properties are found, via electrochemical impedance spectroscopy (EIS), to decrease as flow rate (Q) increases, similar to findings for coatings in NaCl solution. EIS modulus decreases more for coatings in deionized water than those in electrolyte solution. Topographical characterizations show severe coating blistering in deionized water immersion with higher Q, but not in electrolyte solutions. Deionized water is thus believed to accelerate more aggressively the degradation than electrolyte solution. [Copyright &y& Elsevier]

In this study, we investigate computationally the low-Reynolds-number droplet motion in a square micro-channel, a problem frequently encountered in microfluidic devices, enhanced oil recovery and coating processes. The droplet deformation and motion are determined via a three-dimensional spectral boundary element method for wall-bounded flows. The effects of the flow rate, viscosity ratio and droplet size on the interfacial dynamics are identified for droplets smaller and larger than the channel size and for a wide range of viscosity ratio. Owing to the stronger hydrodynamic forces in the thin lubrication film between the droplet interface and the solid walls, large droplets exhibit larger deformation and smaller velocity. Under the same average velocity, a droplet in a channel shows a significantly smaller deformation and higher velocity than in a cylindrical tube with the same size, owing to the existence of the corners' area in the channel which permits flow of the surrounding fluid. A suitable periodic boundary implementation for our spectral element method is developed to study the dynamics of an array of identical droplets moving in the channel. In this case, the droplet deformation and velocity are reduced as their separation decreases; the reduction is influenced by the flow rate, viscosity ratio and more significantly the droplet size. [ABSTRACT FROM AUTHOR]

Abstract: Resveratrol is a unique, natural polyphenolic compound with diverse health benefits. In the present study, we attempted to improve resveratrol biosynthesis in yeast by different methods of metabolic engineering. We first mutated and then re-synthesized tyrosine ammonia lyase (TAL) by replacing the bacteria codons with yeast-preferred codons, which increased translation and improved p-coumaric acid and resveratrol biosynthesis drastically. We then demonstrated that low-affinity, high-capacity bacterial araE transporter could enhance resveratrol accumulation, without transporting resveratrol directly. Yeast cells carrying the araE gene produced up to 2.44-fold higher resveratrol than control cells. For commercial applications, resveratrol biosynthesis was detected in sucrose medium and fresh grape juice using our engineered yeast cells. In collaboration with the Chaumette Winery of Missouri, we were able to produce resveratrol-containing white wines, with levels comparable to the resveratrol levels found in most red wines. [Copyright &y& Elsevier]

A 3D spectral boundary element method is employed to compute the dynamics of a single droplet in a microconfined shear flow. Comparisons have been made for the motion of an initially spherical droplet near a single wall and that between two parallel plates. Investigations are conducted for the influences of the capillary number, viscosity ratio, and initial location of the droplet on the droplet deformation, orientation, velocities, as well as the transition between the initial rapid deformation and the subsequent relaxation stage. Computational results for the deformation and velocities are compared with analytical predictions. It is found that the analytical predictions are limited for small deformations, large droplet-wall distances, and near equiviscous droplets. [ABSTRACT FROM AUTHOR]

Resveratrol, a compound commonly found in red wine, has attracted many attentions recently. It is a diphenolic natural product accumulated in grapes and a few other species under stress conditions. It possesses a special ability to increase the life span of eukaryotic organisms, ranging from yeast, to fruit fly, to obese mouse. The demand for resveratrol as a food and nutrition supplement has increased significantly in recent years. Extensive work has been carried out to increase the production of resveratrol in plants and microbes. In this review, we will discuss the biosynthetic pathway of resveratrol and engineering methods to heterologously express the pathway in various organisms. We will outline the shortcuts and limitations of common engineering efforts. We will also discuss briefly the features and engineering challenges of other longevity boosting compounds. [ABSTRACT FROM AUTHOR]

The hemodynamic forces on endothelial cells or leukocytes attached to the inner surface of blood vessels affect the physiological behavior of these systems via mechano-transduction or receptor-ligand binding. The present study investigates the relative importance and nature of the two components of the hemodynamic force, i.e., the shear and normal force, on a cell and its vicinity. We consider a wide range of blood vessels (from capillaries to arteries) and cell’s spreading angles. Based on computational investigation and analysis, our study demonstrates that the normal force contributes significantly to the total force on the cell; the influence is much more pronounced in small vessels. We also show that the spreading of the cell on the vessel surface should not be discounted, especially in small vessels. Our results are also applicable to the fluid forces on other protuberances of biological nature attached to vascular vessels (e.g., cancer cells and biofilm) as well as to the fluid forces over protuberances in microfluidics and porous media. [ABSTRACT FROM AUTHOR]

In the present study we describe a novel three-dimensional spectral boundary element algorithm for interfacial dynamics in Stokes flow and/or gravity. The main attraction of this approach is that it exploits all the benefits of the spectral methods (i.e., exponential convergence and numerical stability) with the versatility of the finite element method. In addition, it is not affected by the disadvantage of the spectral methods used in volume discretization to create denser systems. Our algorithm also exploits all the benefits of the boundary element techniques, i.e., a reduction of the problem dimensionality and great parallel scalability. To achieve continuity of the interfacial geometry and its derivatives at the edges of the spectral elements during the droplet deformation, a suitable interfacial smoothing is developed based on a Hermitian-like interpolation. An adaptive mesh reconstructing procedure based on the relevant lengths of the spectral elements is also described. In addition, we consider the inertialess motion of a buoyant droplet left to rise (or sediment) near a vertical solid wall and compare our numerical results with analytical predictions. In our study we emphasize the need for computational studies for the accurate determination of droplet migration near solid walls. [ABSTRACT FROM AUTHOR]

Abstract: Resveratrol is a polyphenolic compound produced by a few higher plants when under attack by pathogens such as bacteria or fungi. Besides antioxidant benefits to humans, this health-promoting compound has been reported to extend longevity in yeasts, flies, worms, fishes and obesity mice. Here we utilized the synthetic scaffolds strategy to improve resveratrol production in Saccharomyces cerevisiae. We observed a 5.0-fold improvement over the non-scaffolded control, and a 2.7-fold increase over the previous reported with fusion protein. This work demonstrated the synthetic scaffolds can be used for the optimization of engineered metabolic pathway. [Copyright &y& Elsevier]

Bubble dynamic behaviors from photoelectrochemical water splitting are key issues in the interfacial mass transport on photocatalyst surface. To date, the interaction between gas bubbles and photocatalyst surfaces has received limited attention, especially bubble bouncing behaviors during photoelectrochemical process have rarely been discussed in the literature. In this study, a visualization method by external chopping disturbance was proposed to regulate bubble dynamic behaviors on the TiO 2 photoelectrode surface during photoelectrochemical reaction. Under continuous irradiation, the dominant physics in each bubble growth phase were inertia-controlled, the transition from diffusion-controlled to chemical reaction-controlled and the chemical reaction-controlled. Under rhythmically chopping, the bouncing bubble grew only while in contact with the photoelectrode and its trajectory was approximately to a spiral shape. The proportion of the acceleration stage was very small during the overall rising process, and the bubble rise velocity can be approximately as constant. The main reason for the bubble no longer return is that the rising distance is too far to feel the Marangoni attraction force. • A method to regulate bubble dynamic behaviors by chopping is proposed. • Single bubble evolution is controlled by different dominant physics in each phase. • Bouncing bubbles keep spherical and grow only while in contact with photoelectrode. • The motion trajectory of bouncing bubble is approximately to a spiral shape. • Main reason for no longer return is the bubbles rise too far to feel attraction. [ABSTRACT FROM AUTHOR]

Anticancer nanomedicines have been proven effective in mitigating the side effects of chemotherapeutic drugs. However, challenges remain in augmenting their therapeutic efficacy. Nanomedicines responsive to the pathological abnormalities in the tumor microenvironment (TME) are expected to overcome the biological limitations of conventional nanomedicines, enhance the therapeutic efficacies, and further reduce the side effects. This Review aims to quantitate the various pathological abnormalities in the TME, which may serve as unique endogenous stimuli for the design of stimuli-responsive nanomedicines, and to provide a broad and objective perspective on the current understanding of stimuli-responsive nanomedicines for cancer treatment. We dissect the typical transport process and barriers of cancer drug delivery, highlight the key design principles of stimuli-responsive nanomedicines designed to tackle the series of barriers in the typical drug delivery process, and discuss the "all-into-one" and "one-for-all" strategies for integrating the needed properties for nanomedicines. Ultimately, we provide insight into the challenges and future perspectives toward the clinical translation of stimuli-responsive nanomedicines. [ABSTRACT FROM AUTHOR]

In this study, we experimentally investigate the large-scale vortex pair formed by droplets in the spanwise direction of the flow field of a hollow cone spray injected transversely into a gaseous crossflow. Experiments are conducted in a square channel for a wide range of spray and crossflow conditions. The spatial and velocity distributions of the spray droplets for different cross-sections of the flow field in terms of different flow conditions are measured through flow visualization. Three parameters, namely, vortex vorticity, depth of vortex core, and distance between both vortex cores, are used to characterize the counter-rotating vortex pair (CVP) formed by droplets. The crossflow Reynolds number, (initial atomized) droplet Reynolds number, and number of droplets injected per unit time are all found to significantly influence the features of droplets CVP. We newly define the spray-to-crossflow momentum flux ratio ( J ∗) based on the injected momentum flux of initial atomized droplets. Accordingly, we develop a set of correlations for predicting the features of droplets CVP based on experimental measurements and the Buckingham π theorem. The results show that these correlations well predict all measured conditions. The results of this study should provide insights into the dynamics of spray droplets in a crossflow and an understanding of the large-scale mixing between a hollow cone spray and a crossflow. [ABSTRACT FROM AUTHOR]

Genetically modified microbes have had much industrial success producing protein-based products (such as antibodies and enzymes). However, engineering microbial workhorses for biomanufacturing of commodity compounds remains challenging. First, microbes cannot afford burdens with both overexpression of multiple enzymes and metabolite drainage for product synthesis. Second, synthetic circuits and introduced heterologous pathways are not yet as 'robust and reliable' as native pathways due to hosts' innate regulations, especially under suboptimal fermentation conditions. Third, engineered enzymes may lack channeling capabilities for cascade-like transport of metabolites to overcome diffusion barriers or to avoid intermediate toxicity in the cytoplasmic environment. Fourth, moving engineered hosts from laboratory to industry is unreliable because genetic mutations and non-genetic cell-to-cell variations impair the large-scale fermentation outcomes. Therefore, synthetic biology strains often have unsatisfactory industrial performance (titer/yield/productivity). To overcome these problems, many different species are being explored for their metabolic strengths that can be leveraged to synthesize specific compounds. Here, we provide examples of non-conventional and genetically amenable species for industrial manufacturing, including the following: Corynebacterium glutamicum for its TCA cycle-derived biosynthesis, Yarrowia lipolytica for its biosynthesis of fatty acids and carotenoids, cyanobacteria for photosynthetic production from its sugar phosphate pathways, and Rhodococcus for its ability to biotransform recalcitrant feedstock. Finally, we discuss emerging technologies (e.g., genome-to-phenome mapping, single cell methods, and knowledge engineering) that may facilitate the development of novel cell factories. [ABSTRACT FROM AUTHOR]

The crude oil is in most cases accompanied with water and natural gas. For this reason, it is important to understand the rheology of the oil emulsion. There are already many works relating to rheology of the oil/water emulsion. However, studies on high-pressure rheology of water/crude oil emulsion in the presence of CH4are rare. In this work, light crude oil with characteristics of high wax content, which is typical in Northwest China, was studied. The rheology of water/crude oil emulsion in the presence of CH4under various conditions were fully studied. The results show that the crude oil emulsion showed obvious characteristics of non-Newtonian fluid at a lower temperature. Before water fraction reached a certain limit, the viscosity increases with the increase of water fraction, when water fraction reaches and exceeds the limit the emulsion viscosity drops with the increase of water fraction. The shear stress–shear rate curves become similar as the increase of temperature, indicating the decreasing effect of temperature on the relation between shear stress and shear rate. When the pressure reaches 8 MPa, the shear stress measured with CH4in the system surpasses that measured without CH4. At higher pressure, CH4shows obvious influence on the rheology. [ABSTRACT FROM PUBLISHER]

In this article we report a facile method to create a polyaniline (PANI) nanorod/carbon nanoparticle (CNP) composite structure that is suitable for supercapacitor use. A network of CNPs was conveniently produced on the surface of a nickel foam by collecting candle soot above a burning candle. The PANI nanorods were then electrochemically deposited on the CNP network, forming a star-like interconnected 3D structure. As a comparison, MnO 2 particles were also deposited on the CNP network to produce a broccoli-like structure. The electrochemical properties of these two composites were examined using cyclic voltammetry, cyclic charge-discharge, and electrochemical impedance spectroscopy. The two electrodes exhibited different electrochemical behaviors: high capacitance at low current densities and marked deterioration at high ones for CNPs/PANI and relatively low but stable capacitance for CNPs/MnO 2 . The reasons for this distinction were discussed based on the structures and material properties of the electrodes. [ABSTRACT FROM AUTHOR]

This paper presents a study on single bubble photogenerated by 376 nm laser light at TiO 2 nanorod-array electrode during photoelectrochemical (PEC) conversion. The surface properties of TiO 2 nanorod-array electrode were investigated at first for a better understanding of the three-phase contact line behavior. The results indicate the light-induced hydrophilic effect of TiO 2 nanorod-array electrode under illumination, which makes bubble tend to be pseudo-sphere shape during attaching on electrode. The experimental investigation on photogenerated bubble at TiO 2 nanorod-array electrode shows that there is a linear relationship between cubic root of time and bubble radius, demonstrating the gas products from the surface reaction transferring into bubble through bubble bottom according to the analysis of the relative size between bubble and effective solid surface. Furthermore, the coupling effects between bubble and irradiance were discussed. The bubble scatter effect on light causes a local light intensity increase at electrode surface area on both sides of bubble, and leads to photocurrent increase especially at small bubble size. While the increase of irradiance causes the parameters of bubble evolution period, dissolved gas concentration for nucleation and departure diameter increase, but leads to bubble evolution rate and incident photon conversion efficiency (IPCE) decrease. These results suggest a lower irradiance is preferred for a higher PEC conversion efficiency from the aspects of IPCE and bubble evolution rate. [ABSTRACT FROM AUTHOR]

In this study, evolution and final state of particle size distribution (PSD) of TiO 2 /water suspension were described by a modified population balance equation considering both natural convection and Brownian motion. The calculation was verified by experimental measurement of scanning electron microscope and Laser particle analyzer. Based on the predicted PSD, Rayleigh scattering theory (for d < 4 λ ) and Fraunhofer diffraction theory (for d > 4 λ ) were then employed to determine the scattering and absorption coefficients of TiO 2 /water suspensions with various particle concentrations and at various light wavelengths. UV–Vis investigation showed that the predicted optical properties of TiO 2 /water suspension considering PSD are in much better agreement with the experimental results than that without considering PSD, at all particle concentrations investigated. It is traditionally accepted that for colloid suspension the scattering coefficient can be neglected compared to the absorption coefficient and therefore the extinction, which is the combination of the absorption and scattering coefficients, can be approximately replaced by the absorption coefficient. However, our finding indicates that, when particle aggregation is considered, the scattering coefficient of TiO 2 /water suspension could be much higher than the absorption coefficient. Consequently, using the absorption coefficient alone to replace the extinction coefficient even at long wavelengths could result in significant calculation errors and is not recommended. [ABSTRACT FROM AUTHOR]

Experiments concerning the flow regimes observed in gas-liquid two-phase flows in a long-distance pipeline-riser system were carried out and analyzed in this paper. The test loop with 0.075 m inner diameter consisted of a 314 m horizontal pipeline, followed by a 25 m downward-inclined pipe, and finally a 21.5 m riser pipe. An industrial-scale global flow regime map including 5 flow regimes was derived from differential pressure measurements in the riser and was used as a reference for improvements. Electrical capacitance volume tomography installed in the horizontal section was used to reconstruct the phase interface and calculate the average gas void fraction (GVF). An appropriate model for this system was selected by comparing the experimental GVF with different, widely used models. The occurrence of severe slugging flow (SS) can be predicted accurately using an improved model involving additional corrections that consider pipeline length, accurate GVF calculation, and gas density. This study supports the development of a suitable SS prediction model enabling safe design, operation, and control of practical systems. • The phase interface was reconstructed by ECVT to obtain gas void fraction (GVF). • Experiments on gas-liquid two-phase flow in an industrial-scale system were conducted. • Effect of pipeline length/GVF/gas density on severe slugging was analyzed. • An improved model to predict occurrence of severe slugging was derived. [ABSTRACT FROM AUTHOR]

Besides their wide existence in various industrial processes, nanoscale particle suspensions are also the important media for some emerging technologies such as photocatalytic hydrogen production. The circulating flow properties of the nanoparticles in the fluid are of great concern for their practical use. In our study, a modified experimental system was set up based on Malvern laser particle analyzer that can estimate the nanoparticle concentration and size distribution in a laminar nanoparticle circulating flow. We found that the particle concentration and size distribution were periodical oscillation with time in such flow. Understanding the oscillation mechanism is capable of promote the energy efficiency of photocatalytic hydrogen production. A simulation based on Discrete Element Method (DEM) was conducted to understand this particular oscillation mechanism by studying the single particle movement and trajectory properties in the solid-liquid suspension. The simulation results agree well with the tendency obtained by the experimental results and are capable of better understanding the oscillation characteristics. The simulation results also reveal that the nanoparticles tend to gather in the middle region (the higher velocity region) of the tube after several cycles. Moreover the gravity is of great significance in the circulating flow of solid-liquid suspension because the particle swarms tend to distribute a little below the axial center line of the straight tube. These obtained results are credible for understanding the nanoscale particle transport phenomenon in many natural or industrial processes. In particular, our results are helpful for the understanding and effective control of the movement and distribution of photocatalyst particles in the tubular photocatalytic reactor, which is believed to significantly affect the incident radiation distribution and finally the energy conversion efficiency of the photocatalytic process. • A simulation based on DEM method is conducted to predict the particles transport; • A periodical oscillation of the particles volume fraction and size is predicted; • The trajectory and behaviour of single particle was studied by the simulation; • This simulation can be extended to other applications of particulate system. [ABSTRACT FROM AUTHOR]

Pea (Pisum sativum L.) has been a promising source of plant-based protein, but better protein functionalities are needed by the food industry. In this study, pea protein isolate (PPI) was extracted by alkaline extraction-isoelectric precipitation method, followed by spray-drying. The functional attributes of PPI, as affected by four different cultivars (Agassiz, Spider, Trapeze and ND Trial) and four alkaline extraction pH (8.5, 9.0, 9.5, 10.0), were firstly studied. Results showed that cultivars had significant impacts on the solubility, emulsifying capacity and stability, and foaming capacity and stability of PPI, while alkaline extraction pH only affected emulsifying stability, and foaming capacity and stability. The protein structural characteristics were then evaluated using sodium dodecyl sulfate polyacrylamide gel electrophoresis, size exclusion chromatography with multi-angle static light scattering, quantification of sulfhydryl/disulfide group and Fourier transform infrared spectroscopy analyses. The contents of legumin, aggregates, exposed sulfhydryl group and β-turn structure were different among PPI of different cultivars. Additionally, increasing alkaline extraction pH from 8.5 to 10.0 resulted in PPI with reduced surface tension, which contributed to their better foaming capacity and stability. Image 1 • Pea protein isolates (PPI) from different cultivars differed in functionality. • The structure and composition of PPI were different among cultivars. • The lower legumin/vicilin ratio, the better functionality of PPI. • PPI prepared by higher alkaline extraction pH had better foaming properties. [ABSTRACT FROM AUTHOR]

• Yarrowia has shown the potential for producing complex terpenoids. • Yarrowia may hold multiple cytosolic acetyl-CoA and NADPH generation pathways. • Metabolite channeling is a key consideration in terpene pathway engineering. • Knowledge gaps exist in compartment-specific fluxes for utilizing alternative carbon sources (e.g., lipids). • Metabolic shift, genetic stability, and dimorphism in large-scale Yarrowia fermentation need further studies. Yarrowia lipolytica has emerged as an important non-model host for terpene production. However, three main challenges remain in industrial production using this yeast. First, considerable knowledge gaps exist in metabolic flux across multiple compartments, cofactor generation, and catabolism of non-sugar carbon sources. Second, many enzymatic steps in the complex-terpene synthesis pathway can pose rate-limitations, causing accumulation of toxic intermediates and increased metabolic burdens. Third, metabolic shifts, morphological changes, and genetic mutations are poorly characterized under industrial fermentation conditions. To overcome these challenges, systems metabolic analysis, protein engineering, novel pathway engineering, model-guided strain design, and fermentation optimization have been attempted with some successes. Further developments that address these challenges are needed to advance the Yarrowia lipolytica platform for industrial-scale production of high-value terpenes, including those with highly complex structures such as anticancer molecules withanolides and insecticidal limonoids. [ABSTRACT FROM AUTHOR]

• The phase interface in the upstream horizontal section was reconstructed using ECVT. • Upstream interface drop and slugging are induced by the flow in the riser. • Lockhart-Martinelli model is found to be best and is used for improved correlation. • An improved void fraction prediction model is proposed for pipeline-riser systems. • This improved model leads to considerably reduced prediction errors. This paper introduces the application of void fraction prediction models (25 models total) from a simple horizontal pipe to a complex, real pipeline. The flow mechanism in the pipeline-riser system is explained based on the upstream phase interface and differential pressure in the downstream riser. The transition boundaries of "stratified to intermittent flow" and "stratified smooth to stratified wavy flow" in the horizontal section were predicted well by the models based on simple pipes. Electrical capacitance volume tomography was used to obtain the upstream void fraction just before the downstream gas-liquid eruption, α 1 , or during multiple cycles, α 2. The difference between α 1 and α 2 are ranging between −10 % and 5 %. Finally, an improved correlation is proposed based on the model found to be best (Lockhart and Martinelli, with error values (root mean square error (RMSE) and mean absolute percentage error (MAPE)) of about 12 % and 18 %); the corresponding error levels (RMSE and MAPE) amount roughly to 5 % and 10 %, respectively. The improved model also delivers a good prediction for α 1 when separating in two flow regimes. Overall, the finally proposed correlation reads and is found superior in terms of accuracy to all previously published correlations. [ABSTRACT FROM AUTHOR]

The development of heavy oil has become increasingly important due to the demand of human society for energy. The in-situ upgrading is a technology using transition metal catalyst to reduce heavy oil viscosity to enhance oil recovery. This work revealed the Cu atoms of CuSO 4 entered the heavy oil molecules to increase viscosity, and the NaOH can inhibit this viscosity increasing effect to improve the catalyst activity of CuSO 4. The composite catalyst NaOH/CuSO 4 was proved to decrease the viscosity by 81.43% at 300 °C. The further analysis showed that the effect of NaOH was attributed to the competitive reaction mechanism and production of the Cu and CuO x. These conclusions are helpful to understand the aquathermolysis upgrading mechanism and develop the inexpensive and efficient composite catalyst. • The NaOH improves catalyst activity of CuSO 4 to decrease the heavy oil viscosity efficiently. • This work revealed the inefficiency of CuSO 4 is attributed to the increasing Cu content of heavy oil. • This work revealed the NaOH can inhabit the disadvantage reaction of CuSO 4 and might produce high active materials. [ABSTRACT FROM AUTHOR]

Bubble evolution from photo(electro)catalytic water splitting plays a vital role in the interfacial mass transport on photocatalyst surface. However, little success has been achieved to optimize this process, restricted by the poor understanding. Herein, taking photoelectrochemical (PEC) water splitting over a titanium dioxide (TiO 2 ) nanorod-array electrode as a model system, experiments were performed to study single oxygen bubble dynamics by combining electrochemical measurement and high-speed microscopic imaging. The experimental results indicate that the departure of bubble from photoelectrode is retarded by light irradiation, but the traditional bubble departure criterions fail to predict the bubble departure diameters especially in high light intensity. Additional analysis reveals that the light irradiation causes the Marangoni force acting on the evolving bubble, because it induces temperature rise and generates dissolved gas. A modified force balance model for bubble departure from photoelectrode was developed by adding Marangoni force. This modified model that takes account of the light-induced temperature rise and the dissolved gas, agrees well with the experimental data and can be extended to other photo(electro)catalytic reactions. [ABSTRACT FROM AUTHOR]

• SCW/CO 2 /N 2 mixture injection is proposed for heavy oil recovery. • A core experimental system of SCW/CO 2 /N 2 flooding is developed. • SCW/CO 2 /N 2 flooding is divided into three stages. • CO 2 and N 2 provide the driving force and eliminate gravity override. • SCW/CO 2 /N 2 flooding can both enhance oil recovery and upgrade oil quality. Exploitation of heavy oil is critical for mitigating the energy crisis. However, conventional thermal recovery methods cannot completely exploit the potential of heavy oil owing to its high viscosity and heavy distillates. A new technology is proposed with reference to CO 2 – and N 2 -assisted supercritical water (MGA-SCW) injection for heavy oil recovery. In this study, an experimental apparatus was developed to simulate the MGA-SCW flooding process and test its feasibility. MGA-SCW injection remarkably enhanced oil recovery, increased the oil production rate, and improved the oil quality. For MGA-SCW flooding at 25 MPa and 400 °C, the recovery factor approached 95 %, and the oil viscosity decreased by 32 %; the light distillate fraction (180–350 °C) increased from 11 to 15 %. The dynamic process of MGA-SCW flooding is divided into three stages: pressure difference, thermal, and miscible drives. This technology can be applied to the development and utilization of offshore heavy oil fields. [ABSTRACT FROM AUTHOR]

Numerical simulation of free surface multi-fluid flow is a challenging problem owning to the interaction between deformed interface and free surface. In this paper, a multiphase particle solver (free surface multiphase moving particle semi-implicit method, FS-MMPS) is developed to predict the early spreading flow of spilled oil where exist the oil–water interface and air–oil/air–water free surface. First, a multiphase virtual particle model is proposed to substitute the inaccurate free surface boundary condition for multiphase flow in conventional MPS methods. Specifically, virtual particles of different liquid phases are compensated outside free surface so that the pressure of free surface particles can be solved from pressure Poisson equation, thereby improving the accuracy of multi-fluid interaction at free surface. Meanwhile, a pressure gradient model based on the coupling of Taylor series expansion and dynamic specification of particle stabilizing term (PST) is proposed to simultaneously enhance accuracy and depress instability caused by multiphase virtual particles. Experiments of early spreading of thick oil slicks and continuous oil spill from a damaged tank are conducted for validation and demonstration of the accuracy and stability enhancements in 2D. Finally, the effects of traveling wave and continuous spilling on oil spreading are investigated to show the capability of the proposed method. The spreading of thick oil slicks is accelerated when wave height increases or wave length decreases, and the largest increase of spreading rate accelerated by traveling wave is 14%. [ABSTRACT FROM AUTHOR]

Direct contact condensation of jets in fluid has been widely applied in many industrial applications owing to the low requirement of driving potential and high efficiency of heat and mass transfer. Here, experiments are carried out to investigate the velocity field characteristics of the turbulent jet induced by direct contact condensation of steam jet in crossflow of water in a vertical pipe. Visual equipment is specially invented to investigate the velocity field characteristics by using Particle Image Velocimetry (PIV) measurement technique. The high intensity laser light reflected by the pure steam region just outside the nozzle-exit brings out severe damage to the CCD camera. To solve this technical problem, a black plate is adopted to shield the pure steam region. According to the contours of the velocity fields and streamlines, the influences of jet momentum ratio, jet Reynolds number and water temperature on the jet flow field are explored. The jet centerline trajectory equations in exponential form are established based on the local maximum mean velocity. By introducing the jet Reynolds number and jet momentum ratio, the correlation for prediction of jet centerline trajectory equations is proposed, and the predicted results are within 30% of the experimental data. The reciprocal of the local maximum mean velocity and the half-width of the jet are proportional to the downstream coordinate along the jet velocity centerline trajectory. The scaled velocity field complies with the self-similarity principle. [ABSTRACT FROM AUTHOR]

• An expression for single bubble coverage on the photoelectrode surface is proposed. • The mass transfer is dominated by single-phase free convection in low current density. • The mass transfer coefficient peaks in the inertia-controlled bubble growth phase. • Periodic illumination accelerates bubble detachment and enhances mass transfer. The limitation of the transfer of gas products within the photocatalytic system is the key to the efficiency of the water splitting, which is directly influenced by the bubble evolution process on the catalyst surface. In this study, the entire process of bubble evolution on the surface of a superhydrophilic TiO 2 photoelectrode was simultaneously measured visually and electrochemically. The bubble growth and detachment characteristics were investigated under different laser powers and constant bias voltages. An expression for the bubble coverage characterized by the bubble radius and photocurrent, which is applicable to the photoelectrocatalytic water splitting, was proposed to accurately obtain the mass transfer coefficient during bubble evolution. The mass transfer mechanism of gas product transfer in the low current density range dominated by single-phase free convection was revealed. The mass transfer coefficient was found to increase in the inertia-controlled phase and decrease in the chemical reaction-controlled phase of bubble growth. Furthermore, a method to accelerate bubble detachment from the photoelectrode surface by periodic illumination was proposed, which could significantly enhance the gas product transfer process. [Display omitted] [ABSTRACT FROM AUTHOR]

Aortic stenosis is the most common valvular heart disease. Assessing the contribution of the valve as a portion to total ventricular load is essential for the aging population. A CT scan for one patient was used to create one in vivo tricuspid aortic valve geometry and assessed with computational fluid dynamics (CFD). CFD simulated the pressure, velocity, and flow rate, which were used to assess the Gorlin formula and continuity equation, current clinical diagnostic standards. The results demonstrate an underestimation of the anatomic orifice area (AOA) by Gorlin formula and overestimation of AOA by the continuity equation, using peak velocities, as would be measured clinically by Doppler echocardiography. As a result, we suggest that the Gorlin formula is unable to achieve the intended estimation of AOA and largely underestimates AOA at the critical low-flow states present in heart failure. The disparity in the use of echocardiography with the continuity equation is due to the variation in velocity profile between the outflow tract and the valve orifice. Comparison of time-averaged orifice areas by Gorlin and continuity with instantaneous orifice areas by planimetry can mask the errors of these methods, which is a result of the assumption that the blood flow is inviscid. [ABSTRACT FROM AUTHOR]

• The interface wave in the horizontal section before the riser was studied by an ECVT. • Flow regime transition boundaries shift to lower velocities due to the riser. • The period of hydraulic jump is consistent with that of severe slugging flow. • The hydraulic jump upstream is mainly caused by pressure fluctuations of the riser. This paper describes experiments conducted on the gas–liquid two-phase flow characteristics in a pipeline-riser system under 1 MPa. The hydraulic jump phenomenon (HJP) in the upstream horizontal section was quantitatively studied using electrical capacitance volume tomography (ECVT). Flow regime transition boundaries were shifted to lower gas and liquid velocities due to the impact of the riser at the end of the horizontal pipe. The HJP's period is consistent with that of severe slugging flow; additionally, the liquid slug production and the gas–liquid eruption stages always occur before the HJP in the upstream horizontal section. The Pearson correlation coefficient between the HJP upstream and the pressure fluctuations in the three main structures (horizontal, downward, and riser sections), the period consistency, and the sequential relationship between them were analyzed to verify that the pressure fluctuations in the downstream riser were the main cause of the HJP upstream. [ABSTRACT FROM AUTHOR]

Centipeda minima (CM), the dried whole plant of Centipeda minima (L.) A. Braun and Aschers, has been used as a traditional Chinese medicinal herb for thousands of years for the treatments of rhinitis, sinusitis, cough and asthmatic diseases. This review aimed to evaluate the therapeutic potential of CM by summarizing its phytochemistry, pharmacology, clinical application and safety. This review summarizes the published studies on CM in the Chinese Pharmacopoeia and literature databases including PubMed, Web of Science, Baidu Scholar, Wiley and China Knowledge Resource Integrated Database (CNKI), as well as the research articles on the phytochemistry, pharmacology, clinical application and safety of CM. A total of 191 compounds have been isolated and identified from CM, including terpenes, flavonoids, sterols, phenols, organic acids and volatile oils. In addition, the pharmacological effects of CM, such as anti-cancer, anti-inflammatory and anti-bacterial activities, have also been evaluated by both in vitro and in vivo studies. The signaling pathways and mechanisms of action underlying the anti-cancer effects of CM have been revealed. Clinical applications of CM mainly include rhinitis and sinusitis, gynecological inflammation, cough, as well as asthma. CM is a medicinal herb that possesses many therapeutic effects. Cutting-edge technology and system biology could provide us a more comprehensive understanding of the therapeutic effects, constituting components and toxicity of CM, which are the prerequisites for its translation into therapeutics for various disease treatments. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Mechanically flexible mats consisting of electrospun carbon nanofibers (ECNFs) were prepared by first electrospinning aqueous mixtures containing a natural product of alkali lignin together with polyvinyl alcohol (PVA) into composite nanofiber mats followed by stabilization in air and carbonization in an inert environment. Morphological and structural properties, as well as specific surface area, total pore volume, average pore size, and pore size distribution, of the lignin-based ECNF mats were characterized; and their electrochemical performances (i.e., capacitive behaviors) were evaluated by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The lignin-based ECNF mats exhibited outstanding performance as free-standing and/or binder-free electrodes of supercapacitors. For example, the ECNFs made from the composite nanofibers with mass ratio of lignin/PVA being 70/30 (i.e., ECNFs (70/30)) had the average diameter of ∼100 nm and the Brunauer–Emmett–Teller (BET) specific surface area of ∼583 m2 g−1. The gravimetric capacitance of ECNFs (70/30) electrode in 6 M KOH aqueous electrolyte exhibited 64 F g−1 at current density of 400 mA g−1 and 50 F g−1 at 2000 mA g−1. The ECNFs (70/30) electrode also exhibited excellent cycling durability/stability, and the gravimetric capacitance merely reduced by ∼10% after 6000 cycles of charge/discharge. [Copyright &y& Elsevier]

• Monodispersed HCSs with tunable cavity size were synthesized through a thermal-etching process without template. • The "inside-out" oriented thermal etching process was induced by the "core-shell" differentiated chemical structures of CSs. • HCSs exhibited a SISG efficiency as high as 88.9%, which outperforms most of the previously reported carbon-based materials. • The delicate heat management contributes to the significantly improved SISG efficiency. Hollow carbon spheres (HCSs) with controllable morphology and structure have received considerable attention in the field of energy conversion and storage. Herein, monodispersed HCSs with cavity sizes tuned from 100 nm to 800 nm and shell thickness from 450 nm to 50 nm were successfully synthesized through a unique template-free thermal-etching method. It was evidenced that the dynamically controllable synthesis of HCSs was attributed to the "inside-out" oriented thermal oxidation etching of carbon spheres (CSs) induced by the differentiated "core-shell" chemical structures. Comparing to CSs, the obtained HCSs exhibited much increased efficiency for solar-driven interfacial steam generation (SISG), reaching as high as 88.9%, which outperforms most of the previously reported carbon-based materials. It was then demonstrated that the rational heat management for both photothermal and thermal-evaporation conversion is essential to achieve satisfying SISG efficiency. Depending on the increasing cavity sizes, HCSs presented gradual increases in both photothermal conversion and thermal-evaporation performances, mainly attributed to the improved light absorption and the delicate heat management, respectively. However, the further increase in cavity size resulted in excessive heat loss and presented decreased thermal-evaporation performance. This work provides an alternative and promising approach to the reasonable design of hollow nanostructures with delicate heat management for efficient SISG as well as other solar energy conversion applications. Hollow carbon spheres with tunable cavity was synthesized by an oriented thermal etching of hydrothermally synthesized carbon spheres, which exhibited excellent solar steam generation performances, with delicate heat management in both photothermal conversion and thermal-evaporation processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Summary: As the second enzyme of the non-mevalonate terpenoid pathway for isopentenyl diphosphate biosynthesis, DXP reductoisomerase (DXR, EC: 1.1.1.267) catalyzes a committed step of the MEP pathway for camptothecin (CPT) biosynthesis. In order to understand more about the role of DXR involved in the CPT biosynthesis at the molecular level, the full-length DXR cDNA sequence (designated as CaDXR) was isolated and characterized for the first time from a medicinal Nyssaceae plant species, Camptotheca acuminata. The full-length cDNA of CaDXR was 1823bp containing a 1416bp open reading frame (ORF) encoding a polypeptide of 472 amino acids. Comparative and bioinformatic analyses revealed that CaDXR showed extensive homology with DXRs from other plant species and contained a conserved transit peptide for plastids, an extended Pro-rich region and a highly conserved NADPH binding motif in its N-terminal region owned by all plant DXRs. Phylogenetic analysis indicated that CaDXR was more ancient than other plant DXRs. Tissue expression pattern analysis revealed that CaDXR expressed strongly in stem, weak in leaf and root. CaDXR was found to be an elicitor-responsive gene, which could be induced by exogenous elicitor of methyl jasmonate. The functional color complementation assay indicated that CaDXR could accelerate the biosynthesis of carotenoids in the Escherichia coli transformant, demonstrating that DXP reductoisomerase plays an influential step in isoprenoid biosynthesis. [Copyright &y& Elsevier]

Background: β-Ionone is a fragrant terpenoid that generates a pleasant floral scent and is used in diverse applications as a cosmetic and flavoring ingredient. A growing consumer desire for natural products has increased the market demand for natural β-ionone. To date, chemical extraction from plants remains the main approach for commercial natural β-ionone production. Unfortunately, changing climate and geopolitical issues can cause instability in the β-ionone supply chain. Microbial fermentation using generally recognized as safe (GRAS) yeast offers an alternative method for producing natural β-ionone. Yarrowia lipolytica is an attractive host due to its oleaginous nature, established genetic tools, and large intercellular pool size of acetyl-CoA (the terpenoid backbone precursor). Results: A push–pull strategy via genome engineering was applied to a Y. lipolytica PO1f derived strain. Heterologous and native genes in the mevalonate pathway were overexpressed to push production to the terpenoid backbone geranylgeranyl pyrophosphate, while the carB and biofunction carRP genes from Mucor circinelloides were introduced to pull flux towards β-carotene (i.e., ionone precursor). Medium tests combined with machine learning based data analysis and 13C metabolite labeling investigated influential nutrients for the β-carotene strain that achieved > 2.5 g/L β-carotene in a rich medium. Further introduction of the carotenoid cleavage dioxygenase 1 (CCD1) from Osmanthus fragrans resulted in the β-ionone production. Utilization of in situ dodecane trapping avoided ionone loss from vaporization (with recovery efficiencies of ~ 76%) during fermentation operations, which resulted in titers of 68 mg/L β-ionone in shaking flasks and 380 mg/L in a 2 L fermenter. Both β-carotene medium tests and β-ionone fermentation outcomes indicated the last enzymatic step CCD1 (rather than acetyl-CoA supply) as the key bottleneck. Conclusions: We engineered a GRAS Y. lipolytica platform for sustainable and economical production of the natural aroma β-ionone. Although β-carotene could be produced at high titers by Y. lipolytica, the synthesis of β-ionone was relatively poor, possibly due to low CCD1 activity and non-specific CCD1 cleavage of β-carotene. In addition, both β-carotene and β-ionone strains showed decreased performances after successive sub-cultures. For industrial application, β-ionone fermentation efforts should focus on both CCD enzyme engineering and strain stability improvement. [ABSTRACT FROM AUTHOR]