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A typical charging profile for the li-ion batteries in electric vehicles (EVs) includes a constant current (CC) charging stage and a constant voltage (CV) charging. This letter proposes a simple and reconfigurable topology for CC and CV outputs in an EV wireless charging system. The proposed system can be switched to series-series (S-S) topology for CC output and inductor-capacitor-capacitor-series (LCC-S) topology for CV output. Only one relay is introduced, unlike existing solutions where many passive components and relays are utilized for reconfiguration. Also, there is no need for frequency variation to achieve the shift of CC and CV. An experimental prototype is implemented to validate the proposal.

In recent years, the requirement for landscaping has become increasingly stringent as large-scale bridge construction continues in China, and a conventional bridge scheme creation process has the d...

It is not completely understood fatigue strength at this time due to its complex formation mechanism. Therefore, in order to address this issue, machine learning has been used to examine the important factors involved in predicting fatigue strength. In this study, a hybrid model was proposed based on the modified bagging method by combining XGBoost and LightGBM, in which the hyperparameters of the models were optimized by a grey wolf algorithm. Moreover, an interpretable method, referred to as Shapley additive explanations (SHAP), was introduced to explain the fatigue strength predictions made by ML models. The SHAP values were calculated, and feature importance of fatigue strength by XGBoost, LightGBM and the hybrid model was discussed. The final results demonstrated that the SHAP method had major potential for interpreting fatigue strength predictions, which would provide constructive guidance for the development of antifatigue steel material in the future.

The aim of this study was to investigate the effects of small interfering RNA (siRNA) targeting human growth hormone receptor (hGHR) combined with 5-fluorouracil (5-FU) on the hepatic metastasis of colon cancer. The animal model of liver metastases using human SW480 colon cancer cells was established on BALB/c mice and the siRNA interfering plasmid targeting hGHR gene was constructed. The tumor-bearing mice were randomly divided into the saline control, plasmid, growth hormone (GH), 5-FU, 5-FU+plasmid and 5-FU+plasmid+GH groups. The liver metastasis in each group was observed. All the animals showed liver metastases and using siRNA-interfering plasmid treatment the incidence of liver metastases was significantly reduced in the tumor groups compared to the saline or GH group. The combined treatment of interfering plasmid and 5-FU slightly decreased the incidence of liver metastases in the tumor groups compared to the plasmid alone or 5-FU alone treatment, although the findings were not statistically significant. On the basis of the combination of interfering plasmid and 5-FU, the additional GH did not increase the incidence of liver metastases (P>0.05), but improved the weight loss of the mice (P

In this paper, we review the related studies on the interphase mass transfer process accompanied with Marangoni effect in liquid-liquid systems. The Marangoni effect is triggered by the local variation of interfacial tension and influenced by many factors, such as the physicochemical properties of the system, the solute concentration and the bulk flow. The onset criterion of the Marangoni effect has been discussed extensively via theoretical analysis and experimental verification, but a unified and universal criterion was still not developed due to the complex system geometry and boundary conditions. When the Marangoni convection occurred, the bulk flow adjacent to the interface was spontaneously disturbed, normally leading to an enhanced mass transfer coefficient. Besides, the surface active agent has been found to affect the solute transport across the interface, by either promoting or inhibiting the Marangoni convection according to the nature of additives.

Aim: To study effects of recombinant human growth hormone (rhGH) on growth hormone-insulin-like growth factor axis (GH-IGFs) of human gastric cancer cell in vivo in order to reveal part mechanism of growth effects of rhGH on gastric cancer. Methods: Nude mice were randomly divided into control group, cisplatin (DDP) group, rhGH group and DDP + rhGH group after human gastric cancer xenograft model of node mice was successfully founded and drugs were used for 6 days. We investigated volume of tumor, inhibitory rate of tumor and cell cycle by slide gauge and flow cytometry. In addition, We also respectively investigated insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) of blood serum of nude mice, IGF-ImRNA, insulin-like growth factor-I receptor (IGF-IR) mRNA and IGFBP-3 mRNA of xenograft of nude mice by enzyme linked immunosorbent assay (ELISA) and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) on the first day of completing use of drugs later. Results: Tumor grew obviously slowly and tumor inhibitory rate obviously rose in DDP group and DDP + rhGH group compared with control group and rhGH group (p p p < 0.05). Expressions of IGF-I mRNA and IGF-IR mRNA were not obviously different in all groups. But expression of IGFBP-3 mRNA obviously increased in rhGH group, DDP group and DDP + rhGH group compared with control group; meanwhile, expression of IGFBP-3 mRNA also obviously increased in DDP + rhGH group compared with control group, DDP group and rhGH group. Conclusion: Our results indicated rhGH in short-time use did not improve proliferation of human gastric cancer cells and its mechanism was possible that rhGH in short-time use raised simultaneously IGF-I and IGFBP-3 of blood serum and increased IGFBP-3 mRNA, but degraded ratio of IGF-I and IGFBP-3 of blood serum in human gastric cancer cells.

In this paper, a hydrostatic model of the surface profile anchored to the upper edge of a vertical cylinder is proposed to explain why coins can float on water surface. The sharp edge of a cylinder is thus modeled as a round smooth surface on which the contact line may be anchored at a position according to the weight of the cylinder. The mathematical model of the surface profile is established based on the hydrostatics and a third order ordinary differential equation is resulted. Numerical solution of the model demonstrates under practical conditions the existence of the surface profiles that provide reasonable uplifting force at the contact line so that the force is available for floating coins on water surface. The proposed model explains the obviously enlarged apparent contact angle and the edge effect in the literature. The numerical simulation is found in very good agreement with the experimental data in the literature. (C) 2012 Elsevier Inc. All rights reserved.

Bi2Te3 powders were synthesized at 453 K from Bi(NO3)3·5H2O and Te by an aqueous chemical method, then bulk material was fabricated by hot pressing at 673 K. To investigate the effect of microstructure on the transport properties of electrons and phonons, the thermoelectric performance of the hot-pressed sample and a zone-melted crystal with similar chemical composition was measured and compared. Strong grain-boundary scattering caused a significant decrease of the thermal conductivity; however, the maximum ZT value of the hot-pressed sample was 0.28, which was lower than that of the zone-melted crystal. Further improvement could be obtained through optimization of both chemical composition and microstructure.

Process intensification is one of the most significant trends in current chemical engineering and process industries. In recent years, the desire to become more “green” in processing has always been tied to the requirement of being profitable. This review discusses the challenges of process engineering and summarizes the key role of fundamentals for green process intensification.

The Marangoni effect is a frequently observed phenomenon of enhancement of interphase mass transfer in liquid-liquid systems. Such an effect, originating front the hydrodynamic instability induced by surface tension sensitivity to surface concentration of transferred solute, is mathematically formulated and numerically simulated for slowly moving single spherical drops in an axisymmetric boundary-fitted coordinate system by solving coupled fluid flow and solute mass transfer equations. Numerical simulation demonstrates the occurrence of the Marangoni effect under typical conditions in liquid-liquid systems, and is in reasonable agreement with the classic theoretical analysis. Sufficient spatial and temporal resolution in simulation reveals the multi-scale interaction of the drop-scale Marangoni effect with the sub-drop-scale local interfacial convection. The effect of solute transfer direction, Peclet number, surface tension sensitivity to solute concentration, and level of random perturbation on surface concentration are investigated numerically. It is shown that the Marangoni effect occurs in the middle stage of a transient interphase mass transfer process, and the Marangoni convection at the interface does not necessarily results in the Marangoni effect of mass transfer enhancement. Besides, the Marangoni effect occurs only when the surface tension sensitivity to the solute concentration variation is above certain critical level. The present axisymmetric simulation of the Marangoni effect provides necessary basis for further work on three-dimensional numerical analysis. (C) 2004 Elsevier Ltd. All rights reserved.

Effects of the aqueous components, pH, concentration of NaCl, and volume ratios of oil-to-water on the desulfurization activity of gram-negative desulfurizing bacterium,Pseudomonas delafleldii R-8, were investigated. R-8 showed high desulfurization activity even with a concentration of NaCl up to 60 g · L−1 or high content of dodecane over 83%. The addition of NADH could increase the desulfurization activity of the whole cells. The desulfurization of DBT could be proceeded in the presence of hydrocarbons with the carbon length ranging from 6 to 16. Among them, the largest specific desulfurization activity was shown in dodecane, the value of which was 1.96 mg · g−1 · h−1 similar to that ofR. erythropolis IGTS8.

Several parameters that influence the dibenzothiophene (DBT) desulfurization by lyophilized cells of Pseudomonas delafieldii R-8 were studied in the presence of dodecane. The aqueous media tested with pH range in 4.6-8.5 made no obvious difference on the desulfurization activity. The rate and extent of desulfurization were strongly dependent on the volume ratio of oil-to-water, DBT concentration and the cell concentration. The specific desulfurization rate of DBT and 4,6-dimethyl DBT (4,6-DMDBT) could reach 11.4 and 9.4 mmol sulfur kg(-1) dry cells (DCW) h(-1), respectively. The desulfurization pattern of DBT was represented by the Michaelis-Menten equation. The kinetic parameters, the limiting maximal velocity (V-max) and Michaelis constant (K-m), for desulfurization of DBT were calculated. (C) 2002 Elsevier Science B.V. All rights reserved.

As Cloud computing has many advantages, it has been widely applied in various fields. As the increase of the number of users, the data volume will be more and more huge, The exponential growth of huge amounts of data causes that cloud disaster backup are increasingly important. This article is to focus on cloud computing environment of disaster recovery, combined with virtualization technology to design and implement scheme of "dual-active" solution and storage strategy based on" dual-active" data center. The network and business part is to realize the zero loss of user data and zero interruption of business.

The forward and backward extraction of bovine serum albumin (BSA) has been studied using mixed reverse micellar systems of cetyl trimethyl ammoniumbromide (CTAB) and alkyl halides (including 1-chlorobutane (R4Cl), 1-bromooctane (R8Br) and 1-iodobutane (R4I)). The addition of alkyl halide R8Br to 50 mmolA CTAB/20% (v/v) hexanol/petroleurn ether reverse micellar system could improve the BSA transfer from the aqueous phase to reverse micellar phase, while the addition of R4Cl or R4I had almost no effect on the BSA transfer. The mixed reverse micelles formed with CTAB and alkyl halides exhibit excellent backward extraction behavior for BSA. The mixed reverse micelles formed with CTAB and R4I can realize the recovery of BSA effectively in a wide range of pH up to or higher than the isoclectric point of BSA. The mixed reverse trucelles formed with CTAB and R4Cl, R8Br or R4I can obviously enhance the BSA backward transfer at low ionic strength with addition of KBr or KCl as electrolyte. The mixed reverse micellar system indicates that it requires less time to reach the mass transfer equilibrium in comparison with the reverse micellar system with CTAB only. The mechanism of backward extraction proposed that with the addition of alkyl halides to CTAB reverse micelles, the hydrophobic interaction between the reverse micelles decreased. (C) 2002 Elsevier Science B.V. All rights reserved.

Hydroformylation of 1-dodecene was studied in a biphasic system using water-soluble rhodium complex, RhCl(CO) (TPPTS)(2) (TPPTS: P(m-C6H4SO3Na)(3)), as catalyst in the presence of cetyl trimethyl ammonium bromide (CTAB) as surfactant to enhance the reaction rate. The reaction was carried out in a batch reactor at pressures from 0.9 to 1.3 MPa and temperatures froth 353 to 373 K. An orthogonal experimental design was adopted to study the effects of operating variables on reaction rate, selectivity and normal/isomeric aldehyde ratio. The optimal reaction conditions were derived by margin and variance analyses. The analysis of mass transfer indicates that in some cases the gas-liquid mass transfer rate is still a controlling factor. An empirical kinetic equation was developed after correcting the effect of mass transfer. Combining mechanisms of homogeneous hydroformylation with interfacial reaction of biphasic hydroformylation, a semi-empirical kinetic equation was also obtained. (C) 2002 Elsevier Science B.V All rights reserved.

The kinetics of RhCl(CO)(TPPTS)(2)/TPPTS catalyzed hydroformylation of propylene was studied by an orthogonal experimental design. The hydroformylation reaction was carried out batchwise in a 500 ml stirred autoclave. The effects of temperature, total pressure, molar ratio of hydrogen/carbon monoxide, partial pressure of propylene, molar ratio of rhodium/TPPTS and concentration of rhodium catalyst on the initial rate of reaction were determined by margin and variance analysis. Several empirical rate equations were proposed to represent the experimental data. The kinetic parameters were evaluated and the activation energy was found in the range of 75 similar to 85 kJ/mol. The regioselectivity of hydroformylation was also determined and the molar ratio of normal/isomeric aldehyde varied from 3.9 to 56.1. 2002 Elsevier Science B.V. (C) All rights reserved.

By using lysozyme, hemoglobin (bovine), and pepsin as the model proteins and copolymer F1110 containing reactive functional groups of amido, sulfonate, and carboxylic acid groups as the flocculating agents, selective precipitation of proteins was performed by using two chemical processes. The experiment shows that the surface charge of copolymer F1110 is closely related to the pH value in solution. The flocculation behaviors of proteins with F1110 can be controlled completely by adjusting pH value in solution, which realizes the selective separation of mixed proteins. In addition, the selective precipitation of the proteins is promoted by a "modified flocculation" process, in two steps with a combination of F1110 and polyacrylamide. The characterization of modified flocculation is closely related to the property of the protein. These studies show a great prospect for selectively separating proteins from a mixture solution using designed polyelectrolytes containing reactive functional groups.

The effect of protein on the absorption and its second derivative spectra of Cibacron Blue 3GA (CB) has been investigated in cationic reversed micelles compared with that in buffer solution. The spectra of CB is red-shifted with the addition of cetyltrimethylammonium bromide (CTAB) in buffer solution due to electrostatic interaction between CB and CTAB, while spectra of CB in the reversed micelles have no significant shift. The anionic CB has electrostatic interactions with cationic CTAB and has affinity interaction with bovine serum albumin (BSA) or lysozyme in the reversed micelles. The second derivative spectra of CB have red-shifted compared with the presence of BSA in the reversed micelles, which might indicate the decrease of the polarity of the CB microenvironment in the reversed micelles. The absorption maximum (lambda(m)) of CB with BSA in the reversed micelles was blue-shifted compared with that in buffer solution at pH < pI, which indicated that the affinity interaction between CB and protein is different from in reversed micelles and aqueous buffer solution. The CB microenvironment in the reversed micelles is more polar than that of buffer solution. The effect of lysozyme and BSA on the absorption spectra of CB in the reversed micelles has the same trend although these proteins differ in molecular weight and pI. (C) 2002 Elsevier Science B.V. All rights reserved.

A novel approach for determining interfacial kinetics by excluding the mass transfer effect accurately by numerical simulation of fluid flow and mass transfer in a chemical reactor is presented. In the presence of surfactant, the biphasic hydroformylation of 1-dodecene catalyzed by water-soluble rhodium, complex in a stirred autoclave under laminar-flow conditions with flat, horizontal gas-liquid and liquid-liquid interfaces was studied. The new approach in the present kinetic study features the numerical simulation of fluid flow and mass transfer to accurately account for the mass transfer resistance involved in chemical reactions. The laminar-flow structure generated by a simple circular disk impeller as well as the concentration distributions of all components in organic and aqueous phases were simulated by computational fluid dynamics and transport phenomena. In combination with experimental results for the biphasic hydroformylation of 1-dodecene under the same reaction conditions as used in the numerical simulations, the interfacial kinetics of the biphasic hydroformylation of 1-dodecene was determined.

The extraction of gold (I) cyanide in polyethylene glycol-based aqueous biphasic systems has been investigated. Almost all of gold (I) cyanide (>96%) was transferred from salt-rich phase into the polyethylene glycol (PEG)-rich phase without addition of any extractant. No significant influence of solution pH on gold (I) cyanide extraction was observed. The aqueous biphasic systems have high capability of extraction. The gold (I) cyanide in the PEG-rich phase can be easily reduced by addition of zinc. The PEG-rich phase could be reused for extraction of gold (I) cyanide without decrease of extraction capability. The PEG/salt aqueous biphasic systems may provide a potential new technique for gold separation from cyanide solutions because all components of systems are virtually nontoxic and nonflammable.

Flocculation of lysozyme with anionic copolymers of acrylamide, acrylic acid, and sodium styrene sulfonate used as flocculants was performed in pursuit of high flocculation efficiency. Two major factors, pH and ionic strength, are used to investigate the relationship of the flocculation behavior of protein by copolymers and the functional group (-COOH, -NH2, -SO3H) compositions of these copolymers. The protein flocculation can be controlled by adjusting pH. In addition, the various copolymers exhibit differing effects on ionic strength induced protein flocculation. FT-Raman spectroscopy was applied to investigate the mechanism of interaction between protein and copolymer. An attempt was made to understand how the pH and ionic strength change the surface chemical characteristics of protein and copolymers, as well as the relationship between the structure of copolymer and the protein flocculation process.

In a boundary-fitted orthogonal coordinate system, the general governing equations for steady and transient axisymmetrical cases of mass transfer in the external region around single buoyancy-driven drops in steady motion under low or intermediate Reynolds number were expanded and numerically solved by the control volume formulation. The simulation results for typical cases were presented and compared well with the data and empirical correlations in the literature. It suggests that the developed mathematical formulation of the external mass transfer for a deformable buoyancy-driven drop is reasonable, and may give reliable simulating results. The analysis of the mass transfer coefficient against the detail of flow near the drop interface shed light to the respective contribution of molecular diffusion, convection and recirculating wake, as to provide information on the characteristic time scale of decaying Sherwood number, and hence, to be Valuable for analyzing and optimizing the solvent extraction operation. (C) 2001 Elsevier Science Ltd. All rights reserved.

The water-induced micellization of poly(oxyethylene-oxypropylene-oxyethyle) block copolymer, Pluronic L92, in p-xylene solution has been investigated by FT-IR spectroscopic technique. The OH stretching band of water has been resolved by deconvolution and Gaussian curve fitting. The solubilized water can be classified into monomer bound water, dimer bound water, free water and trapped water. Each states of water were sensitive to the water to EO molar ratio (Z). Therefore, their variations with the water to EO molar ratio (Z) have been employed for the detection of the reverse micelle formation and structural change. It showed that Pluronic L92 did not form polymolecular micelles when molar ratio water/EO (Z) 0.35. For Z 1.3, the micelle shape could be nonspherical. The water-EO interaction dominated at all water content. As water was added in the Pluronic L92-p-xylene system, the water-water interaction strengthened during micellization and structural change of micelle. In the meantime, the block copolymer molecules showed stronger intermolecular interaction as compared with that before transition. The micellization of Pluronic L92 in p-xylene was explained by the strengthening of the intermolecular interaction of copolymer, which introduced by the water-water interaction. The results confirm the leading role of water in the reverse micelle formation of PEO-PPO-PEO block copolymer. (C) 2000 Elsevier Science B.V. All rights reserved.

Primary amine can be used to separate vanadium(V) from chromium(VI) effectively in weakly alkaline solution by solvation mechanisms, as shown by earlier work. Separation of rhenium(VII) from molybdenum, tungstenfVI) from molybdenun, etc. can be very effectively carried out by using primary amine mixed with neutral donor reagents by synergistic solvation extraction. Experimental results indicate the presence of solvation extraction in addition to the ordinary anion exchange extraction with amines as solvent. Iron present in the sulfuric acid leaching solution as impurity gets extracted into the organic phase and is difficult to strip. Several mixed solvent systems with an amine and a neutral donor cxtractant have been developed for iron removal. These have common feature that the iron in the organic phase can be stripped with dilute sulfuric acid.