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ABSTRACT The interforce between the magnetic composite forward osmosis (FO) membranes and the magnetic draw solution was proposed to reduce the internal concentration polarization (ICP) of FO process, and realized the synergetic permeability improvement of resultant FO membranes. The key factor was the successful fabrication of the Fe3O4 magnetic nanoparticles (MNPs) with small-size and narrow distribution via co-precipitation method. The cellulose triacetate (CTA) magnetic composite FO membranes were fabricated using Fe3O4 as additive via in situ interfacial polymerization, and named CTA-Fe3O4. Dynamic light scattering (DLS) and zeta results showed that the coated sodium oleate on the MNPs explained their reducing aggregation and the stability of various pHs. The MNPs' surface segregation during demixing process resulted in the improvement of hydrophilicity, Fe content and roughness of resultant CTA-Fe3O4 composite FO membranes. Furthermore, the in situ interfacial polymerization resulted in the formation of the polyamide selective layer, and the CTA-Fe3O4 membrane's N content was 11.02% to 11.12%. The permeability properties (FO and pressure retarded osmosis modules) were characterized using 1.0 M NaCl and 100 mg/L Fe3O4 as draw solutions, respectively. The results indicated that the higher concentration of MNPs supplied more interforce and better FO permeability properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44852. [ABSTRACT FROM AUTHOR]

This study aims to evaluate three commercial virtual reality (VR) display devices on the market via a 3D Fitts's task. In addition, a symptom questionnaire was used to assess the severity of cybersickness symptoms induced by these displays. Ten participants performed repetitive pointing tasks over different conditions of varying display devices, movement directions, and indices of difficulty. On the basis of the results, the projection display obtained the best task performance with the lowest movement time and the highest throughput. It had the least symptoms among the three display devices. The HMD gave the worst results in all criteria. The 3D TV could be considered as good as the projection display in task performance but induced slight level of discomfort, fatigue, and eyestrain. These findings not only provided an initial understanding of differences between the 3D TV and the other two familiar display devices in human performance when interacting within a 3D VE but also pointed a direction to effectively improve future VR display technique. [ABSTRACT FROM AUTHOR]

In this present study, the facile approaches of coagulants and in situ free radical polymerization method for modulating configurations and performances of polyvinylidene fluoride (PVDF) membranes are investigated. Configuration images show that the supramolecular aggregates of PVDF-P(PEGMA-r-MMA) caused by in situ polymerization act as "template" of the tuned configurations of the resultant PVDF membranes. During delay demixing process (ethanol coagulant), the confine of the aggregates resulted in shift of the cauliflower nanograins to the stripe-type nanograins. On the other hand, for the membranes prepared from the instantaneous demixing process in water coagulant, the aggregates contributed to the formation of the confined finger-like structures and the globule agglomerates that constructed the whole thickness of the membrane bulk. Furthermore, those narrow distribution supramolecular aggregates and variation coagulants (water and ethanol) also yield the tuned performances. The membranes' improved mechanical properties and limited hydrophilicity improvement are attributed to the strong interconnection between the aggregates. Because of the fore-forming of the P(PEGMA-r-MMA) aggregates with narrow distribution, all PVDF membranes prepared from the two coagulants possess enlarged flux, narrow distributionmean effective pore size (µ), andmolecular weight cut-off. The delay demixing process contributes to the narrower µ andmolecular weight cut-off, as well increased flux. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(vinylidene fluoride) (PVDF) membranes were prepared with various residence times using water-ethanol (50 : 50, mass ratio) and pure ethanol coagulants as first coagulant, respectively. The physical properties of PVDF solution after free radical polymerization were investigated by dynamic light scattering (DLS), scanning electron microscopy (SEM), viscosity, precipitation kinetics, and surface tension. Resultant PVDF membranes were characterized by SEM, contact angle, mechanical properties, and filtration properties. The results showed that the longer residence time in the first coagulant contributed to the filtration properties improvement. Contact angles of the top-surfaces and bottom-surfaces of membranes decreased as residence time increasing in the first coagulant, and the top-surface showed better hydrophilicity than that of the bottom-surface. The pore size distributions of PVDF membranes showed that the dominating demixing process of the casting solution in water-ethanol coagulant was 5 s, and in that of ethanol was 10-15 s. Additionally, the short-time delay demixing process in water-ethanol first coagulant resulted in a thin dense layer near the top surface, and the longer time delay demixing process in that of ethanol contributed to the shift of the inter-globules to the cellular morphology in the case of the residence time increasing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39987. [ABSTRACT FROM AUTHOR]

Objective: To analyze the incidence of benign lesions in Chinese patients undergoing nephrectomies for renal masses identified as localized renal cell carcinoma (RCC) in preoperative imaging. Methods: Between 1999 and 2007, 303 patients (112 female, 191 male) with presumed localized RCC underwent nephrectomy (234 radical nephrectomies and 69 partial nephrectomies). Preoperative computed tomography images and pathological findings were reviewed and analyzed. Results: Pathological examinations revealed 31 (10.2%) benign lesions in the 303 patients. Among these 31 benign lesions, 15 (5.0%) were angiomyolipomas (AML) and only four (1.3%) were oncocytomas. Significantly, 20 (17.9%) of the 112 female patients had benign lesions compared with 11 (5.8%; P = 0.001) male patients. Benign renal lesions were found in five (25.0%) of the 20 patients with renal masses smaller than 2 cm, 13 (13.0%) of the 100 patients with renal masses 2–4 cm in size and 13 (7.1%) of the 183 patients with renal masses larger than 4 cm. Conclusions: Patients in the present study population show a low incidence of benign renal lesions, approximately half of them being AML. Female patients and patients with renal masses smaller than 4 cm are more likely to have benign renal lesions. [ABSTRACT FROM AUTHOR]

The fabrication of transparent Nd3+ ion-doped Lu2O3 ceramics is investigated by pressureless sintering under a flowing H2 atmosphere. The starting Nd-doped Lu2O3 nanocrystalline powder is synthesized by a modified coprecipitant processing using a NH4OH+NH4HCO3 mixed solution as the precipitant. The thermal decomposition behavior of the precipitate precursor is studied by thermogravimetric analysis and differential thermal analysis. After calcination at 1000°C for 2 h, monodispersed Nd3+:Lu2O3 powder is obtained with a primary particle size of about 40 nm and a specific surface area of 13.7 m2/g. Green compacts, free of additives, are formed from the as-synthesized powder by dry pressing followed by cold isostatic pressing. Highly transparent Nd3+:Lu2O3 ceramics are obtained after being sintered under a dry H2 atmosphere at 1880°C for 8 h. The linear optical transmittance of the polished transparent samples with a 1.4 mm thickness reaches 75.5% at the wavelength of 1080 nm. High-resolution transmission electron microscopy observations demonstrate a “clear” grain boundary between adjacent grains. The luminescent spectra showed that the absorption coefficient of the 3 at.% Nd-doped Lu2O3 ceramic at 807 nm reached 14 cm−1, while the emission cross section at 1079 nm was 6.5 × 10−20 cm2. [ABSTRACT FROM AUTHOR]

The title complex, [Cu2(C8H5Cl2O3)4(C4H4N2)] n, crystallizes as a chain of alternating tetra­kis(2,4-dichloro­phenoxy­acetato)dicopper(II) and pyrazine units in which square-pyramidal copper(II) centers are alternately linked by four bridging 2,4-dichloro­phenoxy­acetate anions and a single bridging pyrazine mol­ecule. Both the dinuclear copper unit and the pyrazine ligand have a center of symmetry. [ABSTRACT FROM AUTHOR]

In the title coordination polymer, {[Co(CHO(2))(2)(C(20)H(14)N(4))(H(2)O)(2)]·2H(2)O}(n), the Co(II) atom (site symmetry [Formula: see text]) is coordinated by two formate O atoms, two water O atoms and two N atoms from two 1,4-bis-(1H-benzimidazol-1-yl)benzene ligands (L), resulting in a distorted trans-CoN(2)O(4) octa-hedral coordin-ation environment. The complete L ligand is generated by crystallographic inversion symmetry and serves to bridge the cobalt ions into a chain propagating in [1[Formula: see text][Formula: see text]]. The dihedral angle between the central benzene ring and the imidazole ring system is 38.48 (12)°. O-H⋯O hydrogen bonds involving both the coordinated and uncoordinated water mol-ecules occur and help to link the chains together.

In the title one-dimensional coordination polymer, [Co(C(2)H(3)O(2))(2)(C(26)H(18)N(4))](n), the Co(II) atom (site symmetry 2) is coordinated by two O,O'-bidentate acetate ions and two 4,4'-bis-(benzimidazol-1-yl)biphenyl ligands in a distorted cis-CoN(2)O(4) octa-hedral geometry. The bridging ligand, which is completed by crystallographic twofold symmetry, links the Co(II) atoms into [10] chains. Within the ligand, the dihedral angle between the benzene and benzimidazole rings is 48.31 (8)°.