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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.