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A novel computationally efficient close formation aerodynamic model is presented using the lifting-line theory based on an elliptical lift distribution assumption. Formation aerodynamic effects induced by trailing vortices of a leader aircraft are formulated as functions of both the relative position and orientation between the leader and follower aircraft. The proposed aerodynamics model is validated by comparing the model predictions with published experimental results. The proposed model is considered to be more accurate than the widely used single horseshoe vortex model, and it is at least as accurate as a fundamental vortex lattice model, but the exact knowledge of the lift distribution is not required. Comprehensive analysis is thereafter conducted to investigate the drag reductions in terms of different relative positions, angles of attack, sideslip angles, and leader-to-follower wingspan ratios. Up to 30% loss of the formation benefit is observed, if the optimal region cannot be tracked within 10% wingspan accuracy. In addition, the impact of the relative orientation between leader and follower aircraft is also investigated. [ABSTRACT FROM AUTHOR]

The aim of the present study was to elucidate differentially expressed proteins in lesional tissues of psoriasis vulgaris (PV) and normal tissues. Lesional skin tissues were collected from PV patients, along with normal skin tissues from healthy individuals. The protein content of the samples was extracted and then separated by two-dimensional gel electrophoresis (2-DGE). Any proteins that were differentially expressed in the lesional skin of PV patients compared with the healthy controls were analyzed by mass spectrometry and bioinformatics. In the stratum corneum and dermis of PV patients, the total number of proteins identified by 2-DGE was 1,969±21 and 1,928±49, respectively. Of these, 30 proteins were differentially expressed in the PV patients, of which 14 were identified as: Type 1 keratin cytoskeleton proteins (including K1C10, K1C14, K1C15 and K1C16); the type 2 keratin cytoskeleton protein, K2C1; actin-associated proteins (including ARP3, ACTA and ACTBM); prohibitin; heat shock proteins (HSPB1 and CH60); centrosome protein, CP135; and membrane associated proteins (including ANXA4 and ANXA5). The differential expression of protein between PV lesions and normal tissue can be considered as pathological biomarker. Elucidating the abnormal regulation of these proteins can provide mechanism of the development of PV and may contribute to significant approaches for PV treatments. [ABSTRACT FROM AUTHOR]

Phosphate removal is important for the control of eutrophication, and adsorption may serve as a powerful supplement to biological phosphate sequestration. Here, we develop a new composite adsorbent (denoted as HMO-PN) by encapsulating active nano-Mg(OH)2 onto macroporous polystyrene beads modified with fixed quaternary ammonium groups [CH2N+(CH2)3Cl]. The N+-tailored groups can accelerate the diffusion of target phosphate through electrostatic attractions. The performance of the as-prepared HMO-PN was found to depend on the pH value of an aqueous medium. HMO-PN also exhibits high sorption selectivity toward the target phosphate. Kinetic equilibrium of phosphate adsorption can be achieved within 100 min, and the calculated maximum adsorption capacity is approximately 1.47 mmol/g (45.6 mg/g). Column experiments further show that the effluent concentration of phosphate can be reduced to below 0.5 mg/L (500 BV), suggesting highly efficient phosphate sequestration. Moreover, the exhausted HMO-PN can be readily regenerated using an alkaline brine solution. [ABSTRACT FROM AUTHOR]

Fluoride pollution in waters has engulfed worldwide regions and an excess of fluoride intake always causes skeletal fluorosis. Herein, a novel hybrid nanomaterial ZrP-MPN was fabricated for fluoride retention by encapsulating nano-ZrP onto macroporous polystyrene materials modified with quaternary ammonium groups. The as-obtained materials exhibited favorable removal of fluoride ions from aqueous solution in presence of common anions (SO4 2-/NO3-/Cl-) at high contents. Moreover outstanding sorption properties were also detected by involving series of commercial adsorbents (AA/magnetite/GFH/manganese sands) as references. Such satisfactory performances might be ascribed to the structural design of nanocomposite. (1) the CH2N+(CH3)3Cl groups enhances sorption diffusion and preconcentration in sorbent phase theoretically based on Donnan membrane principle; (2) the embedded ZrP nanoparticles also devotes to the efficient adsorption capacities due to its size-dependent specific properties. Additionally, the exhausted ZrP-MPN could be regenerated readily by alkaline solution. Thus, ZrP-MPN was a promising material for fluoride retention in waters. [ABSTRACT FROM AUTHOR]

A novel hybrid nanomaterial was fabricated by encapsulating ZrO2 nanoparticles into spherical polystyrene beads (MPS) covalently bound with charged sulfonate groups (-SO3-). The resultant adsorbent, Zr-MPS, exhibited more preferential sorption toward Pb(II) than the simple equivalent mixture of MPS and ZrO2. Such observation might be ascribed to the presence of sulfonate groups of the polymeric host, which could enhance nano-ZrO2 dispersion and Pb(II) diffusion kinetics. To further elucidate the role of surface functional groups, we encapsulated nano-ZrO2 onto another two macroporous polystyrene with different surface groups (i.e., -N(CH3)3+/-CH2Cl, respectively) and a conventional activated carbon. The three obtained nanocomposites were denoted as Zr-MPN, Zr-MPC, and Zr-GAC. The presence of -SO3- and -N(CH3)3+ was more favorable for nano-ZrO2 dispersion than the neutral -CH2Cl, resulting in the sequence of sorption capacities as Zr-MPS > Zr-MPN > Zr-GAC > Zr-MPC. Column Pb(II) sorption by the four nanocomposites further demonstrated the excellent Pb(II) retention by Zr-MPS. Comparatively, Zr-MPN of well-dispersed nano-ZrO2 and high sorption capacities showed much faster breakthrough for Pb(II) sequestration than Zr-MPS, because the electrostatic repulsion of surface quaternary ammonium group of MPN and Pb(II) ion would result in a poor sorption kinetics. This study suggests that charged groups in the host resins improve the dispersion of embedded nanoparticles and enhance the reactivity and capacity for sorption of metal ions. Suitably charged functional groups in the hosts are crucial in the fabrication of efficient nanocomposites for the decontamination of water from toxic metals and other charged pollutants. [ABSTRACT FROM AUTHOR]

Background: Ovarian hyperstimulation syndrome (OHSS) is a recognized complication of ovulation induction, occurring in 1-10% of IVF and embryo transfer cycles. While mild OHSS is of no clinical relevance, severe OHSS is a life threatening complication. However, the efficacy of prevalent treatments appeared to be limited. We developed a continuous autotransfusion system with an ultrafiltration instrument for reinfusion the protein of concentrated ascites for the treatment of severe OHSS. Objective: To study the efficacy and safety of using a continuous autotransfusion system for the treatment of severe OHSS. Materials and Methods: 69 patients with severe OHSS who were treated with controlled ovarian hyperstimulation due to infertility from February 2002 to August 2010 in our reproductive center were divided into two groups. One group treated with continuous autotransfusion system with an ultrafiltration instrument which infused the protein of concentrated ascites, called ultrafiltration group, another group were treated with simple-albumin supplement, called albumin group. Several examinational results and adverse effect were compared between the two groups. Results: The volume of urine output after 72h in ultrafiltration group was more than that inalbumin group, the waist circumference and body weight in ultrafiltration group were lower than those in albumin group after 72h. The serum creatinine levels after 72h in ultrafiltration group was still significantly lower than that in albumin group (p<0.05). The ultrafiltration group rarely showed adverse effect compared with albumin group. Conclusion: Autotransfusion of protein in concentrated ascites for the treatment of severe ovarian hyperstimulation syndrome was effective and safe. [ABSTRACT FROM AUTHOR]

The subject study revealed several unique properties of polymer-based zirconium phosphate (ZrP) for lead removal from waters. ZrP particles were impregnated within two porous polymers, namely, a chloromethylated polystyrene (CP) and a polystyrene cation exchange resin (D-001). Both as-prepared hybrid sorbents (designated ZrP−CP and ZrP−001, respectively) were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and a N2adsorption−desorption test at 77 K. As compared to the fresh particles, ZrP impregnated onto CP exhibits a slight increase in sorption capacity, which may result from their nanosized particles after impregnation. More attractively, ZrP−001 displays much higher sorption preference toward lead ions over calcium ions than ZrP, D-001, and ZrP−CP. Such significant phenomena is mainly attributed to the Donnan membrane effect exerted by the immobilized sulfonate groups on D-001 and further validates its potential application for enhanced removal of the toxic metal from contaminated waters. [ABSTRACT FROM AUTHOR]

A novel polymeric hybrid sorbent namely ZrPS-001, was fabricated for enhanced sorption of heavy metal ions by impregnating Zr(HPO3S)2 (i.e., ZrPS) nanoparticles within a porous polymeric cation exchanger D-001. The immobilized negatively charged groups bound to the polymeric matrix D-001 would result in preconcentration and permeation enhancement of target metal ions prior to sequestration, and ZrPS nanoparticles are expected to sequester heavy metals selectively through an ion-exchange process. Highly effective sequestration of lead, cadmium, and zinc ions from aqueous solution can be achieved by ZrPS-001 even in the presence of competing calcium ion at concentration several orders of magnitude greater than the target species. The exhausted ZrPS-001 beads are amenable to regeneration with 6 M HCl solution for repeated use without any significant capacity loss. Fixed-bed column treatment of simulated waters containing heavy metals at high or trace levels was also performed. The content of heavy metals in treated effluent approached or met the WHO drinking water standard. [ABSTRACT FROM AUTHOR]

Phenols were a kind of pollutant in coal chemical wastewater with high concentration and difficult to decompose and have a significant impact on the subsequent biochemical treatment of the wastewater. In addition, phenols were a kind of weak electrolytes that partially dissociation oxidation under weakly alkaline conditions, making recovery more difficult. In order to solve this problem, phenols were extracted from weak alkaline wastewater with a synergistic solvent. First, the interaction between solvents and phenols and the solvent effect of solvents were calculated by quantum chemistry and the synergistic extractant cyclohexanone/1-pentanol was determined to have significant advantages. Moreover, the synergistic extractant was further analyzed through independent gradient model based on Hirshfeld partition analysis, atoms in molecule topology analysis, electrostatic potential analysis. Results indicated that the synergistic extract can provide multiple hydrogen bond interactions with phenol due to the double action sites of the C=O group of ketone and the -OH group of alcohol. In addition, the efficacy of the extractant was validated by multistage extraction, indicating partial dissociation oxidation of hydroquinone to benzoquinone under weakly alkaline conditions, with removal rates of 99.5% and 99.2% for phenol and hydroquinone, respectively. In general, the synergistic extractant can effectively remove phenols. [ABSTRACT FROM AUTHOR]

This paper presents a study concerning ammonia removal from landfill leachate by struvite precipitation with the use of waste phosphoric acid as the phosphate source. The results indicated that the Al3+ ions present in the waste phosphoric acid significantly affected the struvite precipitation, and a removal ratio of ammonia close to that of pure phosphate salts could be achieved. Nevertheless, large amounts of NaOH were necessary to neutralize the H+ present in the waste phosphoric acid. To overcome this problem, a low-cost magnesium source was proposed to be used as well as an alkali reagent in the struvite precipitation. The ammonia removal ratios were found to be 83%, with a remaining phosphate of 56 mg/L, by dosing the low-cost MgO in the Mg:N:P molar ratio of 3:1:1. An economic analysis showed that using waste phosphoric acid plus the low-cost MgO could save chemical costs by 68% compared with the use of pure chemicals. Post-treatment employment of a biological anaerobic filter process demonstrated that the high concentration of Mg2+ remaining in the effluent of the struvite precipitation has no inhibitory effect on the performance of the biological treatment. [ABSTRACT FROM AUTHOR]

The functional groups and site interactions on the surfaces of two-dimensional (2D) layered titanium carbide can be tailored to attain some extraordinary physical properties. Herein a 2D alk-MXene (Ti3C2(OH/ONa)xF2-x) material, prepared by chemical exfoliation followed by alkalization intercalation, exhibits preferential Pb(II) sorption behavior when competing cations (Ca-(II)/Mg(II)) coexisted at high levels. Kinetic tests show that the sorption equilibrium is achieved in as short a time as 120 s. Attractively, the alk-MXene presents efficient Pb(II) uptake performance with the applied sorption capacities of 4500 kg water per alk-MXene, and the effluent Pb(II) contents are below the drinking water standard recommended by the World Health Organization (10 μg/L). Experimental and computational studies suggest that the sorption behavior is related to the hydroxyl groups in activated Ti sites, where Pb(II) ion exchange is facilitated by the formation of a hexagonal potential trap. [ABSTRACT FROM AUTHOR]

New benzimidazole/benzothiazole imide derivatives with different alkyl substituent chains were designed and synthesized. Their gelation behaviors in 22 solvents were tested as novel low-molecular-mass organic gelators. The test showed that the alkyl substituent chains and headgroups of benzimidazole/benzothiazole residues in gelators played a crucial role in the gelation behavior of all compounds in various organic solvents. More alkyl chains in molecular skeletons in present gelators are favorable for the gelation of organic solvents. SEM and AFM observations revealed that the gelator molecules self-assemble into different aggregates from wrinkle, lamella and belt to dot with change of solvents. Spectral studies indicated that there existed different H-bond formation between imide groups and hydrophobic force of alkyl substituent chains in molecular skeletons. The present work may give some insights into design and character of new organogelators and soft materials with special molecular structures. [ABSTRACT FROM AUTHOR]

A special naphthyl-containing Schiff base derivative, N,N'-bis(2-hydroxy-1-naphthylidene)-1,2-phenylenediamine, was synthesized, and its coordination with various metal ions in situ at the air/water interface has been investigated. Although the ligand contains no alkyl chain, it can be spread on water surface. When metal ions existed in the subphase, an interfacial coordination between the ligand and different metal ions occurred in the spreading film, while different Nanostructures were fabricated in the monolayers. Interestingly to note that among various metal ions, only the in situ coordination-induced Cu(II)-complex film showed supramolecular chirality, although the multilayer films from the ligand or preformed complex are achiral. The chirality of the in situ Cu(II)-coordinated Langmuir film was developed due to the special distorted coordination reaction and the spatial limitation at the air/water interface. A possible organization mechanism at the air/water interface was suggested. [ABSTRACT FROM AUTHOR]

In this work, some amide compounds with different aromatic substituent headgroups were synthesized and their gelation self-assembly behaviors in 22 solvents were characterized as new gelators. The obtained results indicated that the size of aromatic substituent headgroups in molecular skeletons in gelators showed crucial effect in the gel formation and self-assembly behavior of all compounds in the solvents used. Larger aromatic headgroups in molecular structures in the synthesized gelator molecules are helpful to form various gel nanostructures. Morphological investigations showed that the gelator molecules can self-assembly and stack into various organized aggregates with solvent change, such as wrinkle, belt, rod, and lamella-like structures. Spectral characterizations suggested that there existed various weak interactions including π-π stacking, hydrogen bonding, and hydrophobic forces due to aromatic substituent headgroups and alkyl substituent chains in molecular structures. In addition, the drug release capacities experiments demonstrated that the drug release rate in present obtained gels can be tuned by adjusting the concentrations of dye. The present work would open up enormous insight to design and investigate new kind of soft materials with designed molecular structures and tunable drug release performance. [ABSTRACT FROM AUTHOR]

Through reducing action of diethylene triam ine and the regula to ry role of 1-hexadecylpyridinium bromide, uniform, monodispersed and stabilized silver nanoparticles were obtained by chemical reduction m etho d in room temperature. The size of the obtained silver particles is about 60 -90 nm. The reaction process of th e form atio n of silver nanoparticle has adistinct color change, varying from colorless to pale yellow and fina lly brownish yellow. The as-prepared silver nanoparticles have showed a relatively good ph otoca ta lytic p ro pe rty on Congo red and Rhodamine B. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that cognitive processes, such as learning and memory, are affected in depression and antidepressant treatment may ameliorate cognitive impairments. Recent studies have shown that curcumin exhibits antidepressant-like effects. The aim of the present study was to determine whether curcumin administration influences chronic unpredictable stress (CUS)-induced cognitive deficits and explores underlying mechanisms. Male Wistar rats were subjected to CUS protocol for a period of 5 weeks to induce depression. The depressive-like behavior was tested using sucrose preference test, open field test and Morris water maze test. Effects of curcumin on brain-derived neurotrophic factor (BDNF) and extracellular signal-regulated kinase (ERK) levels in the hippocampus were also examined. Chronic treatment with curcumin significantly reversed the CUS-induced behavioral and cognitive parameters (reduced sucrose preference and impaired learning and memory function) in stressed rats. Additionally, CUS reduced hippocampal BDNF and ERK levels, while curcumin effectively reversed these alterations. Taken together, our results indicate that the antidepressant-like effects of curcumin in CUS rats are related to its aptitude to promote BDNF and ERK in the hippocampus. [ABSTRACT FROM AUTHOR]

Activated carbon (AC) is a promising catalyst for the air cathode of microbial fuel cells (MFCs) because of its high performance and low cost. To increase the performance of AC air cathodes, the acceleration of OH- transport is one of the most important methods, but it has not been widely investigated. Here we added quaternary ammonium to ACs by in situ anchoring of a quaternary ammonium/epoxide-reacting compound (QAE) or ex situ mixing with anion exchange resins in order to modify ACs from not only the external surface but also inside the pores. In 50 mM phosphate buffer solution (PBS), the in situ anchoring of QAE was a more effective way to increase the power. The highest power density of 2781 ± 36 mW/m2, which is 10% higher than that of the control, was obtained using QAE-anchored AC cathodes. When the medium was switched to an unbuffered NaCl solution, the increase in maximum power density (885 ± 25 mW/m2) was in accordance with the anion exchange capacity (0.219 mmol/g). The highest power density of the anion exchange resin-mixed air cathode was 51% higher than that of the control, indicating that anion exchange is urgently needed in real wastewaters. Excess anchoring of QAE blocked both the mesopores and micropores, causing the power output to be inhibited. [ABSTRACT FROM AUTHOR]

The gelation behaviors of binary organogels composed of aminobenzimidazole/benzothiazole derivatives and benzoic acid with single-/multialkyl substituent chain in various organic solvents were designed and investigated. Their gelation behaviors in 20 solvents were tested as new binary organic gelators. This showed that the number and length of alkyl substituent chains and benzimidazole/benzothiazole segment have played a crucial role in the gelation behavior of all gelator mixtures in various organic solvents. More alkyl chains in molecular skeletons in present gelators are favorable for the gelation of organic solvents. The length of alkyl substituent chains has also played an important role in changing the gelation behaviors and assembly states. Morphological studies revealed that the gelator molecules self-assemble into different aggregates from wrinkle, lamella, belt, to fiber with change of solvents. Spectral studies indicated that there existed different H-bond formation and hydrophobic force, depending on benzimidazole/benzothiazole segment and alkyl substituent chains in molecular skeletons. The prepared nanostructured materials have wide perspectives and many potential applications in nanoscience and material fields due to their scientific values. The present work may also give new clues for designing new binary organogelators and soft materials. [ABSTRACT FROM AUTHOR]

Organic pollution is an ever-growing issue in aquatic environment, Fenton-like processes have gained widespread acceptance due to their high oxidative potential and environmental compatibility. Derivatives of metal-organic frameworks (MOFs) are emerging heterogeneous Fenton-like catalysts, which have advantages of large surface area, diversity of structures, and abundant active sites. This work focuses on the recent advances in MOFs derivatives including metal compounds and metal incorporated carbons for Fenton-like processes. First, preparation strategies, structures and compositions are introduced. And then, the removal of organic pollutant in Fenton, electro-Fenton, and photo-Fenton process catalyzed by MOFs derivative is summarized, respectively. The contents particularly devote efforts to build connections among preparation, structures, compositions, and performance. Furthermore, the mechanisms of improving performance are discussed in detail. Finally, the perspectives of MOFs derivatives toward Fenton-like applications are proposed. • Preparation strategies of MOFs-derived Fenton-like catalysts are summarized. • Links among preparation, structures, compositions, and performance are studied. • MOFs derivatives are effective to activate H2O2 for removal of organic pollutants. • The mechanisms of enhancing performance of MOFs derivatives are highlighted. • The prospects of MOFs derivatives-based Fenton-like processes are addressed. [ABSTRACT FROM AUTHOR]

As a family of hydrophobic ionizable organic compounds, aromatic sulfonates can be present at high levels in industrial wastewaters. They tend to exist as anions over a wide range of pH and cannot be effectively trapped by conventional adsorbents. In the current study, a recyclable acrylic ester polymer (NDA-801) was synthesized for effective removal of aromatic sulfonates from wastewater of high acidity (e.g., pH < 1) and inorganic salts (e.g., ∼5-10% Na2SO4 in mass), for which sodium 2-naphthalene sulfonate (2-NS) was chosen as a representative target contaminant 2-NS uptake onto NDA- 801 increased with the increasing acidity of the solution. The ζ potential of NDA-801 measured at different pH levels as well as batch 2-NS adsorption from methanol/water binary systems demonstrated the favorable roles of electrostatic and hydrophobic interaction in 2-NS adsorption. As compared to a granular activated carbon GAC-1, NDA-801 exhibited much higher removal efficiency and capacity of 2-NS in fixed-bed adsorption. Moreover, the exhausted NDA-801 beads by 2-NS can be completely regenerated by water wash for repeated use, which is more economically desirable than by other regenerants, such as NaOH solution. Continuous column adsorption—regeneration cycles indicated negligible capacity loss of NDA-801 during operation and further validated its feasibility for potential application in associated wastewater treatment. [ABSTRACT FROM AUTHOR]

In the present study we prepared a hyper-cross-linked polymeric adsorbent (NDA-701) possessing a uniquely bimodal pore size distribution for 4-nitrophenol (4-NP) adsorption from water. A macroporous polymeric adsorbent Amberlite XAD-4 and a granular activated carbon GAC-1 were chosen for comparison. NDA-701 exhibited better mechanical strength and higher capacity of 4-NP than XAD-4, which possibly resulted from its hyper-cross-linking nature and micropore structure, respectively. 4-NP adsorption isotherm onto NDA-701 is well described by the Freundlich model, and its better kinetics performance than GAC-1 resulted from its macropore structure After adsorption NDA- 101 was amenable to an entire regeneration by using NaOH solution as regenerant, whereas only ~75% regeneration efficiency was observed for GAC-1. Results of continuous fixed-bed runs in pilot and industrial scale demonstrated that NDA-701 is capable of completely removing 4-NP from chemical effluent with no capacity loss, and 4-NP can be readily recovered by further treatment of the concentrated regenerant solution. It is attractive that the value of the recovered 4-NP from chemical wastewater will even engender a surplus after countervailing all the operation cost during field application. [ABSTRACT FROM AUTHOR]