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A semi-rigid bipyrazolyl ligand, 2,5-bis(4′-methylene-1H-3′,5′-diphenylpyrazole)thiophene (H2L), and two of its copper complexes have been prepared. X-ray analysis demonstrates that $$ \left[ {{\text{Cu}}_{2}^{\text{II}} \left( {{\text{H}}_{2} {\text{L}}} \right)_{2} {\text{Cl}}_{4} } \right] $$ (1) is dinuclear, while $$ {\text{Cu}}_{6}^{\text{I}} {\text{L}}_{3} $$ (2) exhibits a trigonal prismatic cage structure in which the cavities are partially filled by THF molecules. Complex 2 emits strong phosphorescence at 77 K with maxima at 493 and 588 nm, which are tentatively attributed to the excited states 3LMMCT and 3MM, respectively. Based on the structural data, it is likely that weak intratrimeric (rather than intertrimeric) CuI···CuI interactions are responsible for the cuprophilicity-dependent emissions.

The semirigid bipyrazolyl and tripyrazolyl ligands, namely 1,4-bis((3,5-diphenyl-1H-pyrazol-4-yl)-methyl)benzene (H2L1) and 1,3,5-tris((3,5-diphenyl-1H-pyrazol-4-yl)methyl)benzene (H3L2), and their Cu(I) complexes (Cu2L1) n (1), Cu4(HL2)2 (2) have been prepared and structurally characterized. Single-crystal X-ray analysis demonstrates that 1 exhibits a 2D structure featuring cyclic trinuclear Cu3pz3 subunits. Complex 2 is a tetranuclear compound in which the tripyrazolyl ligand is partially deprotonated and acts as a μ 4 bridge connecting four Cu(I) atoms.

Six triangular silver(I) or gold(I) 4-chloro/iodo-3,5-diphenyl pyrazolates, as well as a triangular silver(I) 4-methyl-3,5-diphenyl pyrazolate, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Comparison and inspection of the Ag/Au⋯Cl/I distances, geometries of C–Cl/I bonds with respect to the Ag3 or Au3 triangles, and crystal packing diagrams verify the existence of Ag3⋯Cl/I or Au3⋯I interactions in some of the structures of the trimers, which are strong enough to impart a substantial effect on the spatial arrangement of the trimers in their solid states. Density function theory (DFT) calculations on the trimers give the molecular electrostatic potential (MEP) surfaces and HOMO/LUMOs, which support that the observed M3⋯X structural motifs can be understood on the basis of a weak acid–base interaction having contributions from both ionic δ+⋯δ− attraction and covalent LUMO–HOMO overlap. Calculations also show the existence of the so-called “σ-hole” and the secondary effect to it on the halogen atoms; the structural roles played by them were discussed based on the crystal structures.

Compound ceramic coatings with the main crystal phase of Al2TiO5 (as-coated samples) were prepared in situ on the surface of Ti-6Al-4V alloy by means of pulsed bi-polar micro-arc oxidation (MAO) in an NaAlO2 solution. The coated samples were calcined in argon and air at 1000 oC, respectively. The phase composition, surface and section morphology, and element contents of the ceramic coatings were investigated by X-ray diffractometry (XRD), Scanning electron microscopy (SEM) and X-ray fluorescence spectroscopy (XRF). The samples were treated in argon and the as-coated ones were calcined in air at 1000 oC to study the anti-oxidation properties of the samples. The results show that Al2TiO5 had been decomposed in an hour and transformed into α-Al2O3 and rutile TiO2 in air. However, Al2TiO5 had been decomposed in four hours in argon and the final coating surface was completely composed of α-Al2O3. The content of Al2O3 was decreased from outside to inside layers and Ti2O3 was formed in the coating. Furthermore, the morphology of the ceramic coatings after the calcination was different. The coatings calcined in argon were finer; the grains and pores were smaller than those in air.

In this paper,the motion planning problem for mobile robot is addressed. Motion planning (MP) has diversified over the past few decades to include many different approaches such as cell decomposition, road maps, potential fields, and genetic algorithms. Often the goal of motion planning is not just obstacle avoidance but optimization of certain parameters as well. A motion planning algorithms based on Rapidly-exploring random Tree(RRT) is present in the paper. Then the RRT algorithm has been extended which combines the SLAM algorithm.The Extend-RRT-SLAM has been simulated in MobileSim.Simulation results show Extend-RRT-SLAM to be very effective for robot motion planning.

This paper is concerned with Q-learning , a very popular algorithm for reinforcement learning ,for obstacle avoidance through neural networks. The principle tells that the focus always must be on both ecological nice tasks and behaviours when designing on robot. Many robot systems have used behavior-based systems since the 1980’s.In this paper, the Khepera robot is trained through the proposed algorithm of Q-learning using the neural networks for the task of obstacle avoidance. In experiments with real and simulated robots, the neural networks approach can be used to make it possible for Q-learning to handle changes in the environment.

Nanostructured surface layer was produced on Ti-6Al-4V alloy by surface mechanical attrition treatment(SMAT) technique, and the composite ceramic coatings of surface nanocrystallization/micro-arc oxidation(SNC/MAO) were prepared on the nanocrystallized surface of Ti-6Al-4V alloy by pulsed single-polar micro-arc oxidation in NaAlO2 solution. XRD, SEM and TEM techniques were used to investigate the phase and surface morphology of ceramic coatings and the influences on the surface state of the alloys. Meantime, the mechanical properties of Ti alloys were measured by tensile test. The results show that after the SMAT treatment for a short period of time, the surface layer was refined into ultrafine grains. The influences of the SMAT technique on the surface morphology of the ceramic coatings were also studied. The ceramic coatings are mainly composed of Al2TiO5, more compact and less porous than those untreated. The mechanical properties of Ti-6Al-4V alloy by SMAT technique are improved, compared with those untreated by SMAT technique.

Ceramic coatings with the main crystalline of TiO2 were prepared on Ti-6Al-4V alloy by pulsed bi-polar Micro-arc Oxidation (MAO) in Na2SiO3 solution. The coated samples were calcined in argon under 1000oC. The phase composition, morphology and element content of the ceramic coatings were investigated by XRD, SEM and EDS. The results showed that the main components of the coatings are TiO2 and amorphous substances, after oxidation in argon, SiO2 was crystalized in coating. The content of elements in the coatings both changed a little.

To observe analgesic effect of scalp acupuncture on labor.Seventy primiparae with term pregnancy and monocyesis were randomly divided into scalp acupuncture group treated by acupuncture at the Shengzhi area of scalp, and control group by no treatment. Pain grades before and after scalp acupuncture were evaluated with the pain 4-grade rating criteria stipulated by WHO, and the active stage and the second birth process, the Apgar scores of new-born and postpartum hemorrage amount were compared between the two groups.The labor pain with 1 to approximately 2 grades was found in 33 cases in the scalp acupuncture group, and 2 cases in the control group with very significant difference between the two groups (P0.01); the active stage was (130.70 +/- 74.16 ) min and the second birth process was (40.70 +/- 21.65) min in the scalp acupuncture group, and (166.15 +/- 62.65) min and (53.30 +/- 26.93) min in the control group, respectively, with significant differences between the two groups (all P0.05); and there were no significant differences in Apgar score of new-born and postpartum hemorrhage amount.Scalp acupuncture has a better analgesic effect in vaginal delivery with no adverse effect on the mother and infant.