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In this paper, we propose a weighted harmonic Golub-Kahan-Lanczos algorithm for the linear response eigenvalue problem (LREP). Convergence properties are established for the error bounds of the approximate eigenpairs. Moreover, we consider a practical thick-restart procedure to reduce the computational and memory costs and present a weighted harmonic Golub-Kahan-Lanczos algorithm with deflated restarting. Numerical tests show the efficiency of our new algorithms.

Structured simulation environments are widely used in the research of robots. Combining with a kind of structured simulation environment, we proposed a new map building method based on image processing in this study. Firstly, the binary road network is extracted from the image by image processing, which is then thinned with improved Zhang parallel thinning algorithm. Then, Shi–Tomasi algorithm is adopted to detect corners from the obtained thinning road network. To get the connectivity between corners, we proposed a thinning-line searching method. Finally, we stored the obtained environment information in the form of adjacency list to represent the topology of the road network. The experiment was conducted to test our method: A topological diagram of the simulation environment was rebuilt. The experimental results showed that the proposed mapping method is effective and practical.

Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is commonly used as an antibacterial agent in various industrial products and is often detected in wastewater effluent. Comparison was made for triclosan degradation by photolysis and TiO2 photocatalysis (under UV irradiation (125 W)) based on analysis of transformation products, together with ecotoxicity evaluation. The morphology of the TiO2 was characterized by X-ray diffractometry (XRD) and field emission gun-scanning electron microscopy (FEG-SEM). Triclosan quantitation was performed by high performance liquid chromatography (HPLC). The optimal condition was obtained using a response surface model and desirability profile. The initial concentration of triclosan used in all the experiments was 10 mg L-1 to achieve comprehensive identification of transformation products. The optimal experimental condition was 30 mg L-1 TiO2 at pH 10. The photocatalytic system achieved > 99% triclosan degradation at 30 min of reaction. The mineralization rates by photolysis and photocatalysis were 25 and 90%, respectively. A total of 27 transformation products were identified using liquid chromatography quadrupole time of flight mass spectrometry (QTOF MS), being that 25 were new structures, not previously reported in the literature. Ecotoxicity assays demonstrated that triclosan and some of the major transformation products did not cause deleterious effects towards Lactuca sativa and Daphnia magna after 16 h of treatment.

5-(Trifluoromethyl)-2-thiazolamine is a key intermediate for manufacturing numerous pharmaceuticals and chemicals. Here, a low-cost, one-pot multicomponent domino synthetic route has been reported for the synthesis of 5-(trifluoromethyl)-2-thiazolamine, which was successfully prepared from 3-bromo-1,1,1-trifluoro-2-propanone, phosphorus pentasulfide and cyanamide in the presence of sodium carbonate with the yield of 56%.

As passively mode-locked fiber lasers based on Nonlinear Polarization Rotation(NPR)have the problem of low stability and difficulty to self-start into a mode-locking state during operation,an online automatic mode-lock circuit was designed to adjust the laser in real time to get a stable modelocked output.In the design,the signal from NPR passively mode-locked laser was transformed to an electrical pulse signal with a high speed photoelectric detector,and it was amplified and shaped linearly to be received by the Micro Computer Unit(MCU)to count.Then the MCU distinguished the state of the laser based on quick mode-lock judge algorithm and adjusted the electric controlled polarization controller(PC)on the fiber laser automatically.The experiment results show that for the NPR modelocked fiber laser with a repetition rate of 6.238MHz,the automatic mode-lock circuit can distinguish the losing lock in 6ms,and can find and get into the mode-lock state in 10.24sautomatically.ForNPR passive mode-locked fiber lasers with repetition rate lower than 16 MHz,this automatic modelock circuit can get into a stable mode-locked state quickly or restart immediately if the mode-lock state is lost for some reasons,which reaches the design requirements and shows advantages of simple structures,low costs,low powers,and high reliability.

Phenolic tert-butyldimethylsilyl (TBDMS) ethers can be deprotected to yield phenols in excellent yield using sodium cyanide (NaCN) as catalyst in ethanol. The deprotectation of various phenolic TBDMS ethers were found to be very convenient, fast, high yielding and chemoselective.

In this paper, the quaternion matrix equations XF # AX = BY and XF # A = BY are investigated. For convenience, they were called generalized Sylvesterquaternion matrix equation and generalized Sylvester-j-conjugate quaternion matrix equation, which include the Sylvester matrix equation and Lyapunov matrix equation as special cases. By applying of Kronecker map and complex representation of a quaternion matrix, the sufficient conditions to compute the solution can be given and the expressions of the explicit solutions to the above two quaternion matrix equations XF # AX = BY and XF # A = BY are also obtained. By the established expressions, it is easy to compute the solution of the quaternion matrix equation in the above two forms. In addition, two practical algorithms for these two quaternion matrix equations are give. One is complex representation matrix method and the other is a direct algorithm by the given expression. Furthermore, two illustrative examples are proposed to show the efficiency of the given method.

High resolution mode-selective excitation in the mixture of C6H6 (992cm−1) and C6D6 (945 cm−1) is experimentally achieved by adaptive femtosecond pulse shaping based on the genetic algorithm (GA), and second harmonic generation frequency-resolved optical gating (SHG-FROG) is adopted to characterize the original and optimal laser pulses, and its mechanism is experimentally validated by tailoring the frequency components of the pump pulses at the Fourier plane. It is indicated that two-pulse coherent mode-selective excitation of the Raman scattering mainly depends on the effective frequency components of the pump pulse related to specific molecular vibrational mode. The experimental results have attractive potential applications in the complicated molecular system.

A Zr56.2Ti13.8Nb5.0Cu6.9Ni5.6Be12.5 bulk metallic glass composite with enhanced plasticity by in situ formed bcc β-Zr solid solution was prepared by water quenching. The ductile β phase with a volume fraction of about 30% possesses a developed dendritic morphology. The composite exhibits a pure plastic strain of 10.2% combined with a large elastic strain limit of 2% and a high ultimate strength of 1778 MPa upon room-temperature compression. Microscopic observation shows numbers of wave-like shear bands distributed on the surface of the compressive samples.

An optimal feedback control of two-photon fluorescence in the ethanol solution of 4-dicyanomethylene-2-methyl-6-p-dimethyl-amiiiostryryl-4H-pyran (DCM) using pulse-shaping technique based on genetic algorithm is demonstrated experimentally. The two-photon fluorescence of the DCM ethanol solution is enhanced in intensity of about 23%. The second harmonic generation frequency-resolved optical gating (SHG-FROG) trace indicates that the effective population transfer arises from the positively chirped pulse. The experimental results appear the potential applications of coherent control to the complicated molecular system.

The brightness of a particular harmonic order is optimized for the chirp and initial phase of the laser pulse by genetic algorithm. The influences of the chirp and initial phase of the excitation pulse on the harmonic spectra are discussed in terms of the semi-classical model including the propagation effects. The results indicate that the harmonic intensity and cutoff have strong dependence on the chirp of the laser pulse, but slightly on its initial phase. The high-order harmonics can be enhanced by the optimal laser pulse and its cutoff can be tuned by optimization of the chirp and initial phase of the laser pulse.

The local atomic configuration of multicomponent chemical short-range order (MCSRO) in NiZr2 has been investigated by means of molecular dynamics simulation (MD) in a wide temperature range. The potential functions for the system based on the embedded atom method are constructed and the parameters are obtained by fitting the structure and properties of NiZr2 crystal. The static structures such as pair distribution functions and the distribution of coordination number have been calculated. The local atomic configurations of the MCSROs in the melt were demonstrated as distorted coordination polyhedron of the compound structure and/or the structure similar to cubooctahedron analogues. It is indicated by the results of MD simulation that above the melting point the atomic packing of long-range order disappears, but the chemical interaction of coordinated atoms still exists, which leads to the formation of various MCSROs with atomic configurations similar to the stable or metastable unit cell of NiZr2 compound. When the system is just melted, many icosahedral polyhedron configurations appear, which decrease as the over-heating temperature increases.

Population transfer in a three-level Λ system is simulated numerically and optimized. Almost complete population transfer from |1 to |3 is achieved by a genetic algorithm while the population in state |2 reached minimum over the entire evolution at the same time. The result shows that the optimal pulse sequence is the well-known stimulated Raman adiabatic passage (STIRAP) scheme. The detuning of pump pulse and Stokes pulse Δp and Δs with the opposite sign and the chirps χp and χs with the same sign are in favour of the complete and robust population transfer for few-cycle laser pulse. Rabi frequencies Ωp and Ωs have insensitive effects on the complete population transfer during a large scope of their ratio when they are large enough.

Mechanical properties of (Zr41.2Ti13.8Cu12.5Ni10Be22.5)100-xNbx bulk metallic glass (BMG) matrix composites reinforced by tungsten fiber (Wf) were investigated by X-ray diffraction, scanning electron microscope (SEM) and so on. The results show that the matrix of the prepared composites remain amorphous after adding Nb with x=1, 3, 5 and 7, at%, and the compressive yield strength and plastic strain increase with the increase of Nb content. The composites with x=7 possess the excellent comprehensive properties, whose compressive yield strength and plastic strain reach 2450 MPa and 20%, respectively.

Mg63Ni22Pr15 metallic glasses are produced by a single roller melt-spinning technique. The hydrogen absorption and desorption capacities are respectively 0.38 and 0.14 wt.% at 313 K obtained by pressure-composition isotherm. The amorphous structure is found to be retained after gaseous hydrogenation. The glass transition temperature, the onset crystallization temperature, and the crystallization temperature of the hydrogenated Mg63Ni22Pr15 metallic glass are 550, 570 and 577 K, respectively, much higher than the corresponding values of 440, 470 and 499 K of the as-quenched sample. This means that dramatic enhancement of thermal stability occurs in Mg63Ni22Pr15 metallic glass due to hydrogenation.

The anisotropy of the current-carrying characteristics of YBCO film fabricated by magnetron sputtering has been investigated. It is shown that the critical current density Jc parallel to the (ab) basal plane is highly anisotropic with respect to theta , the angle between the magnetic field and the c axis. This anisotropy increases with increasing magnetic field. In addition to intrinsic pinning, it is suggested that extrinsic pinning from the planar defects of stacking faults may also contribute to anisotropic pinning. The I-V curves also show anisotropy with theta , and at lower voltages they could be well fitted by the power law V=Aln. The value of n decreases with increasing magnetic field and it could be fitted by n=KH-m. n varies periodically with theta as Jc; the higher Jc is, the larger is n.

The Ar ion implantation induced changes of structure and transport properties of YBa2Cu3O7-x thin films were studied as a function of fluence. Both the zero resistance temperature Tc and the critical current density Jc decrease rapidly with fluence, however, the transition temperature onset almost remains constant at low fluences. At dose of 1.2 × 1013 Ar/cm2, the sample has a metal to semiconductor phase transition. When the fluence further increases, a crystalline to amorphous phase transition occurs, and the sample becomes insulator.

Willowsia guangdongensis sp. nov. Figs 1–20, Tab.1 Type material. HOLOTYPE: male, China, Guangdong Province, Heshan, Heshan Hilly Land Interdisciplinary Experimental Station, Chinese Academy of Sciences, 15.ix.2006, collection number C9522, coll. Jian-xiu Chen, Feng Zhang, and Jigang Jiang. PARATYPES: two females and two males, same data as holotype. Description. Body length: up to 1.86 mm. Color pattern. Ground color pale yellow in alcohol. Eye patches dark blue. Antennae and each segment gradually darker towards apex, Ant. III and IV dark blue. Transverse dark blue band present just behind antennal bases. Body dorsum with scattered blue pigment present on area anterior to eye patches, along lateral margins from thorax to anterior parts of Abd. III, along posterior margins of Abd. IV and V, and on whole Abd. VI. Abd. III and IV respectively with one pair of pale blue patches on dorso-lateral sides. Each leg with two dark blue bands respectively on apex of femur and mid of tibiotarsus (Fig. 1). Head. Antenna 1.9-2.3 times as long as cephalic diagonal. Antennal segments ratio as I: II: III: IV = 1: 1.56–1.78: 1.33-1.56: 2.00–2.22. Antennal apical bulb distinct and unilobed (Fig. 2). Sensory organ of Ant. III as two small rods (Fig. 3). Eyes 8+8, eyes A and B largest and subequal, G and H smallest and subequal. Labral papillae absent. Prelabral and labral setae 4/ 5, 5, 4, all smooth. Outer differentiated seta of labial palp slightly curved, as thick as normal setae, with tip nearly reaching apex of labial papilla (Fig. 4). Subapical seta of maxillary outer lobe large, subequal in length to and slightly thicker than apical one; 3 smooth hairs on sublobal plate (Fig. 5). Labial triangular setae (after Chen & Christiansen 1993) as M 1, r, E, L 1, L 2; all finely ciliate, r 0.5 length of M 1 (Fig. 6). Cephalic dorsal chaetotaxy with four antennal (An), three median (M) and four sutural (S) macrochaetae. Interocular setae (after Mari-Mutt 1986) as pqrst (Fig. 7). Thorax and legs. Dorsal macrochaetae (after Szeptycki 1979) shown in Fig. 8. Th. II with three posterior macrochaetae (p1–3) on each side. Th. III with totally 9 macrosetae, four of them (p5, p6, m6 and m6e) on posterior lateral margin., Published as part of Zhang, Feng & Chen, Guo-Liang Xu Jian-Xiu, 2007, A new species of Willowsia (Collembola: Entomobryidae) from South China, pp. 63-68 in Zootaxa 1645 (1) on pages 64-65, DOI: 10.11646/zootaxa.1645.1.6, http://zenodo.org/record/5103773, {"references":["Chen, J. - X. & Christiansen, K. A. (1993) The Genus Sinella with Special Reference to Sinella S. S. (Collembola: Entomobryidae) of China. Oriental Insects, 27, 1 - 54.","Mari-Mutt, J. A. (1986) Puerto Rican species of Lepidocyrtus and Pseudosinella (Collembola: Entomobryidae). Caribbean Journal of Science, 22 (1 - 2), 1 - 48.","Szeptycki, A. (1979) Morpho-systematic studies on Collembola. IV. Chaetotaxy of the Entomobryidae and its phylogenetical significance. Polska Akademia Nauk, Krakow, Poland, 216 pp."]}

Key to Chinese species of the genus Willowsia 1. Abd. III dorso-central macrochaetae 1+1 .................................................................................. formosana - Abd. III dorso-central macrochaetae more than 1+1................................................................................2 2. Abd. IV dorso-central macrochaetae less than 8+8.................................................................................3 - Abd. IV dorso-central macrochaetae more than 8+8................................................................................5 3. Abd. III dorso-central macrochaetae 3+3 ........................................................................... nigromaculata - Abd. III dorso-central macrochaetae 2+2................................................................................................ 3 4. Prelabral setae ciliate .................................................................................................................. jacobsoni - Prelabral setae smooth....................................................................................... guangdongensis, sp. nov. 5. Abd. III dorso-central macrochaetae 2+2 ............................................................................. guangxiensis - Abd. III dorso-central macrochaetae 3+3 .......................................................................................... shiae, Published as part of Zhang, Feng & Chen, Guo-Liang Xu Jian-Xiu, 2007, A new species of Willowsia (Collembola: Entomobryidae) from South China, pp. 63-68 in Zootaxa 1645 (1) on pages 63-64, DOI: 10.11646/zootaxa.1645.1.6, http://zenodo.org/record/5103773

Zhang, Feng, Chen, Guo-Liang Xu Jian-Xiu (2007): A new species of Willowsia (Collembola: Entomobryidae) from South China. Zootaxa 1645 (1): 63-68, DOI: 10.11646/zootaxa.1645.1.6, URL: https://www.biotaxa.org/Zootaxa/article/view/zootaxa.1645.1.6

Nano-TiO2 powder and TiO2 optical films with photocatalytic activity were prepared by sol-gel progress. Eu3+,Nd3+,Tb3+,Dy3+ were adoped to enhance the photocatalytic activity. The modality of the films was observed with AFM morphology; Three-dimensional picture of TiO2 by AFM (RMS=2.83nm) showed its fine quality. Samples annealed at different temperatures were analyzed with UV-VIS spectroscopy. The results indicated that the absorption of the sample annealed at 500oC is strong because it is composed of anatase and rutile sized about 10~100nm (ref. XRD). XRD was used to analyze the structure of TiO2. The results showed that rutile phase is precipitated as well as anatase of TiO2,and anatase is about 66wt%,and the average dimension is 26nm; Alumina-supported vanadium oxide catalyst (V2O5/Al2O3) was prepared conventionally by impregnating alumina with an aqueous solution of ammonium metavanadate(NH4VO3). Cyclohexanol and cyclohexanone are key reactants for the production of adipic acid and caprolactam. The photo-oxidation of cyclohexane on titanium dioxide and over V2O5/Al2O3 was investigated in neat cyclohexane to synthesize cyclohexanone and cyclohexanol. The reaction also features the photocatalytic activity of Nano-TiO2 and V2O5/Al2O3. The results indicate that titanium dioxide doped with Eu or Tb exhibits the high selectivity to partial oxidation compounds. The characteristic of the reaction over V2O5/Al2O3 is a reasonable (K/A) ketone/alcohol ratio.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Excellent magnetocaloric effect with a maximum entropy change and refrigeration capacity of 17.6 Jkg−1K−1 and 546 Jkg−1, respectively, has been discovered in the Er60Al18Co22 bulk metallic glass under the field of 50 kOe in the temperature range of helium liquefaction. This MCE results from the second-order magnetic transition from the paramagnetic to the ferromagnetic state. Our analysis based on mean-field theory suggests that the excellent MCE is attributed to the strong exchange of magnetic moment in the glassy structure.

The characteristic that nodes can enlist into the network topology freely and independently without any fixed infrastructure makes mobile Ad hoc networks (MANET) widely used in various environments such as disaster rescue, battlefield and so on. Conventional mobile Ad hoc routing protocols usually concentrate on the constrained condition of 'shortest path' with minimum hops measurement. However, related researches show that the path with minimum hops can't provide the minimum end to end delay guarantee. Moreover, recently, Ad hoc network is required to support the delay-sensitive traffic. So the reduction of the end to end delay is a new challenge for Ad hoc networks. To this point, this paper mainly focuses on the node delay and a cross-layer method is used to predict the end-to-end delay. Finally, a new routing protocol Delay Oriented Adaptive Routing (DOAR) is presented, which is based on a 'minimum prediction of delay' mechanism. Simulation results show that the derived path length in the proposed DOAR protocol is slightly higher than that of Dynamic Source Routing (DSR) protocol, but it can significantly reduce the average end-to-end delay in both static and mobile scenarios.

The characteristic that nodes can enlist into the network topology freely and independently without any fixed infrastructure makes mobile Ad Hoc networks (MANET) widely used in various environments such as disaster rescue, battlefield and so on. Traditional Ad Hoc network routing protocols are mainly based on the condition "Shortest Path", and possibly form many local "hotspots" to influence the performance of the network. To this point, a new metric "Leisure Degree" is presented for denoting the transmission state of the node. Based on this metric, a cross-layer design method that involves the MAC (medium access control) layer and the network layer is used to present a new routing protocol Leisure Degree Adaptive Routing (LDAR), which uses a heuristic routing select mechanism to efficiently control the congestion and share the load. This method can improve the performance of the Ad Hoc networks. Simulation results show that LDAR performs much better than the DSR routing protocol under the circumstances of both static networks and mobile networks.

Quadratic Assignment Problem (QAP) is one of the classical combinatorial optimization problems and is known for its diverse applications. This paper presents a new fast ant heuristic for the QAP, the approximate-backbone guided fast ant colony algorithm (ABFANT). The main idea is to fix the approximate- backbone which is the intersection of several local optimal permutations to the QAP. After fixing it, the authors can smooth the search space of the QAP instance without losing the search capability, and then solve the instance using the known fast ant colony algorithm (FANT) which is one of the best heuristics to the QAP in the much smoother search space. Comparisons of ABFANT and FANT within a given iteration number are performed on the publicly available QAP instances from QAPLIB. The result demonstrates that ABFANT significantly outperforms FANT. Furthermore, this idea is general and applicable to other heuristics of the QAP.