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Bacterial foraging optimization (BFO) algorithm is a novel swarm intelligence optimization algorithm that has been adopted in a wide range of applications. However, at present, the classical BFO algorithm still has two major drawbacks: one is the fixed step size that makes it difficult to balance exploration and exploitation abilities; the other is the weak connection among the bacteria that takes the risk of getting to the local optimum instead of the global optimum. To overcome these two drawbacks of the classical BFO, the BFO based on self-adaptive chemotaxis strategy (SCBFO) is proposed in this paper. In the SCBFO algorithm, the self-adaptive chemotaxis strategy is designed considering two aspects: the self-adaptive swimming based on bacterial search state features and the improvement of chemotaxis flipping based on information exchange strategy. The optimization results of the SCBFO algorithm are analyzed with the CEC 2015 benchmark test set and compared with the results of the classical and other improved BFO algorithms. Through the test and comparison, the SCBFO algorithm proves to be effective in reducing the risk of local convergence, balancing the exploration and the exploitation, and enhancing the stability of the algorithm. Hence, the major contribution in this research is the SCBFO algorithm that provides a novel and practical strategy to deal with more complex optimization tasks. [ABSTRACT FROM AUTHOR]

ABSTRACT A fluorescent 'turn-on' probe for Fe3+ was investigated in an aqueous system based on a boron 2-(2′-pyridyl) imidazole complex (BOPIM-dma). BOPIM-dma shows weak or no fluorescence in polar solvents due to twisted intramolecular charge transfer, but the addition of Fe3+ to BOPIM-dma leads to fluorescence switch-on responses. The binding is highly selective to Fe3+ over other metal ions, indicating that BOPIM-dma is a chemodosimeter for Fe3+. Furthermore, the existence of S2O32− could much enhance and stabilize the emission significantly, indicating that the BOPIM-dma/Fe3+/S2O32− complexes are a strong fluorescence system, and can be used as a sensitive detector for Fe3+, with the limit of detection of 6.0 × 10−7 mol L−1. [ABSTRACT FROM AUTHOR]

This paper presents a global optimization algorithm for solving globally the generalized nonlinear multiplicative programming (MP) with a nonconvex constraint set. The algorithm uses a branch and bound scheme based on an equivalently reverse convex programming problem. As a result, in the computation procedure the main work is solving a series of linear programs that do not grow in size from iterations to iterations. Further several key strategies are proposed to enhance solution production, and some of them can be used to solve a general reverse convex programming problem. Numerical results show that the computational efficiency is improved obviously by using these strategies. [ABSTRACT FROM AUTHOR]

This paper presents a global optimization algorithm for solving the signomial geometric programming (SGP) problem. In the algorithm, by the straight forward algebraic manipulation of terms and by utilizing a transformation of variables, the initial nonconvex programming problem (SGP) is first converted into an equivalent monotonic optimization problem and then is reduced to a sequence of linear programming problems, based on the linearizing technique. To improve the computational efficiency of the algorithm, two range reduction operations are combined in the branch and bound procedure. The proposed algorithm is convergent to the global minimum of the (SGP) by means of the subsequent solutions of a series of relaxation linear programming problems. And finally, the numerical results are reported to vindicate the feasibility and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Wetting of ZrO2-3 mol% Y2O3 substrates by a molten Zr55Cu30Al10Ni5 bulk metallic glass forming alloy was studied using a modified sessile drop method at 1133-1473 K in a high vacuum and their interfacial chemistry was investigated. The time variation in the contact angle shows anomalous temperature dependence at 1133-1293 K, i.e., the initial contact angle gradually decreases while the final contact angle increases with increasing temperature. In the range of 1293-1473 K, the contact angle sharply decreases in the initial stage but shows little change in the subsequent long isothermal duration. A distinct reaction layer consisting of substoichiometric ZrO2-x was developed at the interface. The remarkable temperature dependence of the wettability is due to the competition among the adsorption and accumulation of the active atoms such as Zr at the interface, the interfacial reaction, and the release of oxygen from ZrO2. The adsorption of Zr at the triple junction, particularly enhanced by the structural transition of ZrO2, plays an important role in promoting the wettability. In contrast, the oxygen release leads to the oxidation of the active atoms and ready pinning of the triple line, thus deteriorating the wettability. The interfacial reaction may promote the wetting as well, but its role is limited because on the one hand, it consumes the adsorbed active Zr atoms, and on the other, the pinning of the triple line due to the compositional oxidation considerably weakens its function. [ABSTRACT FROM AUTHOR]

Wetting of ZrO2-3 mol% Y2O3 substrates by a molten Zr55Cu30Al10Ni5 bulk metallic glass forming alloy was studied using a modified sessile drop method at 1133-1473 K in a high vacuum and their interfacial chemistry was investigated. The time variation in the contact angle shows anomalous temperature dependence at 1133-1293 K, i.e., the initial contact angle gradually decreases while the final contact angle increases with increasing temperature. In the range of 1293-1473 K, the contact angle sharply decreases in the initial stage but shows little change in the subsequent long isothermal duration. A distinct reaction layer consisting of substoichiometric ZrO2-x was developed at the interface. The remarkable temperature dependence of the wettability is due to the competition among the adsorption and accumulation of the active atoms such as Zr at the interface, the interfacial reaction, and the release of oxygen from ZrO2. The adsorption of Zr at the triple junction, particularly enhanced by the structural transition of ZrO2, plays an important role in promoting the wettability. In contrast, the oxygen release leads to the oxidation of the active atoms and ready pinning of the triple line, thus deteriorating the wettability. The interfacial reaction may promote the wetting as well, but its role is limited because on the one hand, it consumes the adsorbed active Zr atoms, and on the other, the pinning of the triple line due to the compositional oxidation considerably weakens its function. [ABSTRACT FROM AUTHOR]

Two novel poly( p-phenylene vinylene) (PPV) derivatives with conjugated thiophene side chains, P1 and P2, were synthesized by Wittig-Horner reaction. The resulting polymers were characterized by H-NMR, FTIR, GPC, DSC, TGA, UV-Vis absorption spectroscopy and cyclic voltammetry (CV). The polymers exhibited good thermal stability and film-forming ability. The absorption spectra of P1 and P2 showed broader absorption band from 300 to 580 nm compared with poly[( p-phenylene vinylene)-alt-(2-methoxy-5-octyloxy- p-phenylene vinylene)] (P3) without conjugated thiophene side chains. Cyclic voltammograms displayed that the bandgap was reduced effectively by attaching conjugated thiophene side chains. This kind of polymer appears to be interesting candidates for solar-cell applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The Xujiashan antimony deposit is hosted by marine carbonates of the Upper Sinian Doushantuo and Dengying Formations in Hubei Province, South China. Our Sr isotopic data from pre- and syn-mineralization calcites that host the mineralization show that the pre-mineralization calcite displays a narrow range of Sr/Sr ratios (0.7096 to 0.7097), similar to the ratios of the Sinian seawater, and high Sr concentrations (2645 to 8174 ppm). In contrast, the syn-mineralization calcite exhibits low Sr concentrations (785 to 2563 ppm) and high Sr/Sr ratios (0.7109 to 0.7154), which is interpreted as the result of addition of radiogenic strontium during the antimony mineralization. The study of Sr isotopes suggests that their Sr component to the pre-mineralization calcite derived directly from the host rocks (i.e. the Sinian marine carbonates), while radiogenic Sr for the syn-mineralization calcite derived from the underlying Mesoproterozoic Lengjiaxi Group basement through hydrothermal fluid circulation along the major fault that hosts the mineralization. The Pb isotopic ratios of stibnite are subdivided into two groups (Group A and Group B), Group A is characterized by higher radiogenic lead, with Pb/Pb = 18.874 to 19.288, Pb/Pb = 15.708 to 15.805, and Pb/Pb = 38.642 to 39.001. Group B shows lower lead isotope ratios (Pb/Pb = 17.882 to 18.171, Pb/Pb = 15.555 to 15.686, and Pb/Pb = 37.950 to 38.340). The single-stage model ages of Group A are mainly negative or slightly positive values (-258 to 3 Ma), while those of Group B range from 636 to 392 Ma, with an average of 495 ± 65 Ma. In addition, there are positive linear correlations among Pb isotopic ratios. These results suggest that the lead of Group A stibnite was mainly derived from the Sinian marine carbonates, and that of Group B stibnite from the underlying Lengjiaxi Group basement. This conclusion is consistent with the results of the Sr isotopes. These results indicate that the Xujiashan deposit is not syngenetic sedimentary and in situ reworked origin as previously considered. The metal (mainly Sb) of this deposit was not only derived from the Sinian host rocks, but also partly derived from the underlying Mesoproterozoic Lengjiaxi Group basement. [ABSTRACT FROM AUTHOR]

The Kuoerzhenkuola gold deposit is located in the Sawur gold belt in Xinjiang, China. An integrated geological, geochemical and geophysical investigation was carried out in the Kuoerzhenkuola gold deposit, to determine the extension of the principal mineralized system, in the search for new resources. Re-examination of the rocks and structures in the Kuoerzhenkuola area showed that the study area features an elliptical caldera where the gold deposit lies. A re-investigation of the mine geology found that the mineralization at the Kuoerzhenkuola gold deposit is not controlled by the EW-striking regional fault as previously assumed, but by a caldera fracture system locally superimposed by regional faults; the host rocks are andesites and dacites of the Carboniferous Heishantou Group rather than the crypto-explosive breccia of the Devonian Sawurshan Group. Gas components of fluid inclusions from quartz, trace element chemistry of pyrite and fluid inclusions in pyrite, Pb isotopes of pyrite, and whole-rock geochemistry and Pb isotopes of the country rocks are used to study the source of fluids at Kuoerzhenkuola gold deposit. The ore-forming fluids are characterized by low–moderate temperatures and low salinities estimated from fluid inclusion microthermometry. Quadrupole mass spectrometry indicated a CO2-bearing fluid. Inductively coupled plasma–mass spectrometry of the fluid inclusions indicated high Cu (average 70 ppm) for the Au mineralization, whereas the host rocks have low Cu (average 33 ppm), indicating that Cu of the ore-forming fluids originated from magmatic fluid rather than the volcanic rocks. Pb isotopes of ores and host volcanic rocks indicate a similar, mixed source and some Pb could be sourced from the volcanism. This implied that magmatic fluids could play an important role in the Au mineralization process. These new geological findings and the fluids derived mainly from the magmatic fluids suggest that the ore-forming fluids originate at depth, and are transported and precipitated within the caldera fracture system. Thus, we proposed a conceptual target area at depth. A detailed Stratagem EH4 measurement was carried out to test the validity of the conceptual target. Stratagem EH4 soundings over six parallel traverses perpendicular to the mineralized trend showed that the caldera fracture system could extend for approximately 900 m in the dip direction at the center of the caldera, an indication of the presence of potential deep mineralization under the surveyed area. Detailed modeling of the Stratagem EH4 sounding images provided well-defined targets for test drilling. Subsequent test drilling on one of these targets, which extends down 850 m at an angle of 87°, returned encouraging results because four core-intercepts of gold ore bodies at down-hole depths of 40.5–42.0 m, 70.5–73.5 m, 357.0–358.5 m, and 384.5–385.5 m and a long interval gold mineralized body (0–720 m) were encountered. [ABSTRACT FROM AUTHOR]

1. Diabetic neuropathy is a many faceted complication of both type I and II diabetes. The aim of the present study was to investigate the effects of bendazac lysine (BDL), an anticataract drug, on experimental diabetic peripheral neuropathy (DPN) in rats. 2. Diabetes was induced in rats by intraperitoneal injection of 75 mg/kg streptozotocin (STZ) dissolved in 0.1 mol/L citrate buffer (pH 4.4). Bendazac lysine was administered to rats at doses of 50, 100 and 200 mg/kg twice a day for 12 weeks. 3. Diabetic rats without treatment showed hypopraxia, polydipsia, polyuria, slow weight gain, cataract, increased tail-flick threshold temperature, decreased motor nerve conduction velocity (nd induced pathological morphological changes of myelinated nerve fibres. All these symptoms were ameliorated in diabetic rats treated with BDL. Bendazac lysine ameliorated the blood glucose concentration, glycosylated haemoglobin levels and insulin levels in the plasma of diabetic rats, reduced aldose reductase activity in erythrocytes and advanced glycation end-products in both nerves and serum and increase the activity of glutathione peroxidase in the nerves and Na+/K+-ATPase in the nerves and erythrocytes. 4. Bendazac lysine exerts its protective effects against the progression of diabetic peripheral neuropathy in STZ-diabetic rats through multiple mechanisms and is a potential drug for the prevention of deterioration in DPN. [ABSTRACT FROM AUTHOR]

Wetting phenomena and the effect of alumina surface orientation on the wettability in Si/α-Al2O3 system were studied by an improved sessile drop method using R (0112), A (1120), C(0001 ) faces of single crystals and polycrystals at 1723 K in a reducing Ar-3% H2 atmosphere. The contact angles show a vibration behavior for all the single crystals but to a less extent for the polycrystals. The extent of the vibration correlates not only with the reaction intensity but also with the stability of the Si droplet on the alumina surfaces. The interfacial reaction leads to the formation of a series of reaction rings, which is more serious at the single crystal surfaces. More importantly, the wettability is dependent on the alumina surface orientation, with the intrinsic contact angles being about 98±2°, 101±1°, 69±1°, and 98±2°, respectively, for the R(0112), A(1120), C(0001) and polycrystal α-Al2O3 substrates. The much smaller contact angle for molten Si on the C(0001) surface is explained by the favorable reduction in the Si/α-Al2O3 interfacial free energy by the terminated and enriched aluminum atoms at the reconstructed C-(&31radic; times; &31radic;)R±9° surface. The importance of the aluminum presence at the Si/α-Al2O3 interface to the wettability of this system was further demonstrated by a substantial improvement in the wettability of the R (0112)α-Al2O3 substrates by Si-Al alloys. [ABSTRACT FROM AUTHOR]

The wetting behaviors of α-Al2O3 single crystals with three different faces—R(01&1macr;2), A(011&2macr;0), and C(0001)—and polycrystals (PC) by molten aluminum were studied over a wide temperature range using both a conventional and an improved sessile-drop method. The critical factors affecting the wettability, such as temperature, atmosphere, substrate surface roughness, and crystallographic orientation, and the influence from the experimental technique, were thoroughly investigated. The results show that the aluminum surface oxidation and the thickness of the oxide film have a pronounced effect on the wettability, especially at low temperatures. To eliminate this effect, the experimental temperature must be over a critical value. Vacuum favors lowering this value compared with atmosphere, and the improved sessile-drop method, particularly using an impingement-dropping mode (I-mode), helps to weaken this effect by mechanical disruption and removal of the oxide film. However, the dropping distance and the dropping force must be controlled to prevent a receding contact angle. The effects of the substrate surface roughness and temperature are not significant in the case of a clean and a fine-prepared aluminum surface. On the other hand, the effect of the aluminum crystallographic orientation is noticeable and the wettability is in the order of R > A > PC > C. The intrinsic contact angles of the Al/α-Al2O3 system in the temperature range 1000°–1500°C were estimated to be 76&deg–85° for the R and A faces, 88°–100° for the C face, and 77°–90° for the polycrystal, depending on the temperature. [ABSTRACT FROM AUTHOR]

The article discusses the crystal structure of a cyanide-bridge FeII-NdIII bimetallic assembly with a one-dimensional ladder-like chain structure. It describes the molecular structure of iron with atom-numbering scheme, consisting of [FeII(CN)4]2-, [NDIII(NO3)(CH3OH)3]2+ cation and methanol solvent molecule. Also reported is the compound's two-dimensional structure formed via hydrogen bonds between the bimetallic chains of iron.

The coordination geometry of the CoII atom in the title complex, [Co(NCO)2(C12H12N6)2] n or [Co(NCO)2(bbtz)2] n, where bbtz is 1,4-bis­(1,2,4-triazol-1-meth­yl)benzene, is dis­torted octa­hedral, in which the CoII atom lies on an inversion centre and is coordinated by four N atoms from the triazole rings of four symmetry-related bbtz ligands and two N atoms from two symmetry-related monodentate NCO− ligands. The CoII atoms are bridged by four bbtz ligands to form a two-dimensional (4,4)-network. [ABSTRACT FROM AUTHOR]

In the structure of the title complex, [Ni(C17H13N2O2)2(C3H7NO)2] or [Ni(PMBP)2(DMF)2], where HPMBP is 4-benzoyl-5-methyl-2-phenyl-2 H-pyrazol-3(4 H)-one, the CdII atom, which lies on an inversion centre, is in a distorted octa­hedral coordination environment. The metal is coordin­ated by four O atoms from the two symmetry-related chelating PMBP− ligands and O atoms from the two symmetry-related DMF ligands. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title complex, [Ni(C17H13N2O2)2(C3H7NO)2] or [Ni(PMBP)2(DMF)2], where HPMBP is 1-phenyl-3-methyl-4-benzoyl-1 H-pyrazol-5(4 H)-one, the NiII atom, which lies on an inversion centre, is six-coordinated in a distorted octahedral coordination environment by coordinating four O atoms from two symmetry-related chelating bidentate PMBP ligands and two O atoms from two symmetry-related DMF ligands. [ABSTRACT FROM AUTHOR]

The coordination geometry of the CoII atom in the title complex, [Co(NCS)2(C16H14N4)] or [Co(NCS)2(dbz)], where dbz is bis­(benzimidazol-2-yl)ethane, is distorted tetra­hedral; the CoII atom is coordinated by two N atoms from one dbz mol­ecule and two N atoms from two monodentate NCS− anions. [ABSTRACT FROM AUTHOR]

In the title complex, [MnBr2(C24H16N4)], there is a weak C—H⋯Br intermolecular interaction in the crystal structure, giving rise to molecular chains along the a axis. [ABSTRACT FROM AUTHOR]

The title compound, (C16H38N4)[Fe(CN)5(NO)]·2H2O, contains one [Fe(CN)5(NO)]2− dianion, two half [H2tet a]2+ dications (tet a is 5,7,7,12,14,14-hexa­methyl-1,4,8,11-tetra­aza­cyclo­tetra­decane), each lying about an independent inversion centre, and two solvent water mol­ecules, all of which are held together by hydrogen bonds to form a three-dimensional supramolecular framework. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title complex, [Ni(C2N3)2(C3H7NO)2] n or [Ni(dca)2(DMF)2] n, where dca is dicyanamide and DMF is N, N-dimethyl­formamide, each NiII atom is six-coordinated in a distorted octa­hedral coordination environment. Four N atoms from four dca ligands fill the equatorial positions, and two O atoms from two DMF ligands fill the axial positions. The structure is isostructural with [Co(dca)2(DMF)2] n but is not isostructural with [Mn(dca)2(DMF)2] n. The NiII atom and the dicyanamide bridging ligand occupy special positions of symmetry 2/ m and m, respectively. The structure consists of uniform neutral chains where neighbouring NiII atoms are connected through two asymmetric end-to-end dca bridges. [ABSTRACT FROM AUTHOR]