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State of energy (SOE) is a critical index of lithium battery. The problem of the inaccurate available energy and recovered energy of lithium battery affects the accuracy of SOE estimation. In order to solve the problem, this paper proposes a method to estimate the available discharge energy of lithium batteries based on response surface model. In this method, the energy efficiency of lithium batteries in different states is obtained by establishing the relationship model of external charge voltage and external discharge voltage, so as to estimate the actual available energy of lithium batteries in different charge states. On this basis, a correction method based on radial basis function (RBF) neural network is proposed to estimate the actual energy released by the recovered energy when the current direction of the battery is changed. The proposed energy correction method is combined with the adaptive particle filter algorithm to estimate SOE. This method is not limited to the assumption of Gaussian function and can accurately predict the noise variance, so as to improve the estimation accuracy of SOE. Simulations under urban dynamometer driving schedule (UDDS) are conducted, and the result shows that the proposed method can effectively estimate the battery energy and improve the accuracy of SOE estimation.

This paper proposes the concept of an electricity conversion coefficient. The variation of the electricity value, with different charging and discharging currents, is unified into dischargi...

A method based on highly tilted illumination and non-paraxial iterative computation is proposed to improve the image quality of single-shot 3D ptychography. A thick sample is illuminated with a cluster of laser beams that are separated by large enough angles to record each diffraction pattern distinctly in a single exposure. 3D structure of the thick sample is accurately reconstructed from recorded diffraction patterns using a modified multi-slice algorithm to process non-paraxial illumination. Sufficient number of recorded diffraction patterns with noticeably low crosstalk enhances the fidelity of reconstruction significantly over single-shot 3D ptychography methods that are based on paraxial illumination. Experimental observations guided by the results of numerical simulations show the feasibility of the proposed method.

In this paper, we designed and synthesized three benzothiazole-based fluorescent probes L1, L2, and L3 for zinc ion detection. Among various metal ions, only the zinc ion exhibited fluorescence enhancement at 475 nm accompanied by the blue-shift emission wavelength in HEPES buffer solution containing probes. Through titration experiment, the detection limit of L1 for zinc ion sensing was calculated to be as low as 7 nM, which showed a high sensitivity. Furthermore, the confocal laser scanning micrographs of HeLa cells demonstrate good cell permeability of probe L1 and selective detection of zinc ion in living cells. The L1–Zn2+ complex was further used for pyrophosphate (PPi) sensing in HEPES buffer solution, the limit of detection was calculated to be as low as 60 nM. L1–Zn2+ can monitor the enzyme catalyzed degradation process of PPi, thus providing a meaningful way for tracking of zinc ion and pyrophosphate in biological systems.

We have developed a ratiometric fluorescent probe for hypochlorite detection with high selectivity and sensitivity. The probe 1 can rapidly turn into an oxidized form accompanied by the fluorescence changes from yellow to blue only upon the addition of hypochlorite among various reactive oxygen species (ROS) and reactive nitrogen species (RNS). The limit of detection was calculated to be as low as 8.9 nM, which showed good sensitivity to hypochlorite. Furthermore, the confocal laser scanning micrographs of HeLa cells confirmed good cell permeability of probe 1 and its application to selective detecting hypochlorite in living cells.

Radially polarized laser beam amplification up to the 772 mJ using flash-lamp-pumped Nd:YAG amplifiers was demonstrated. In the experiments, a nanosecond radially polarized seed beam was converted from a conventional Q-switched Nd:YAG laser output with a polarization converter and then amplified with two Nd:YAG amplifier stages. A maximum amplification output energy up to 772 mJ was achieved at 10 Hz with a 10-ns pulse, corresponding to an amplification factor of 323%. Excellent conservation of polarization was also obtained during the amplification.

A new dinuclear-copper(II) complex ( Cu-L 2 ) with two ammonium arms based on bis-2-((pyridin-2-ylmethylamino)methyl)phenol as the coordinated unit was synthesized. The complex exhibited high affinity with pyrophosphate (PPi) in aqueous solution. Using pyrocatechol violet (PV) as a colorimetric indicator, the indicator displacement assay (IDA) was carried out to determine the binding constant between the complex and PPi. A ca. 784-fold enhancement was founded when compared Cu-L 2 to ammonium-free counterpart ( Cu-L 1 ) . The new dinuclear complex was successfully used to monitor the hydrolysis of PPi catalyzed by pyrophosphatase (PPase). Furthermore, by employing esculetine as a fluorescent indicator, the complex was also used to detect PPi released during polymerase chain reaction (PCR).

This study aimed to establish a method of producing high-concentration bioethanol from reed with reduced distillation-energy demand. Reed was subjected to a pretreatment combining liquid hot water (LHW) and sodium carbonate with oxygen (LHW–Na2CO3/O2) to increase substrate concentration and further achieve high bioethanol concentration through fed-batch semi-simultaneous saccharification and fermentation (fed-batch S-SSF). An oxygen pressure of 0.8 MPa, a Na2CO3 dosage of 16%, a reaction temperature of 160 °C, and a reaction time of 60 min were determined to be optimal, resulting in the highest bioethanol concentration (66.5 g L−1). Bioethanol concentration increased by 75.9% and resulted in a 76.6% decrease in distillation energy compared with those obtained by single-stage LHW pretreatment at 170 °C. After the LHW–Na2CO3/O2 pretreatment, the rate of lignin removal was 71.4%, and almost all hemicellulose was removed. Lignin and hemicellulose removal weakened the interactions among cellulose, hemicellulose, and lignin. We focused on the maximum utilization of biomass resources and decrease in energy expenditure, which highlighted the potential use of the combined LHW–Na2CO3/O2 pretreatment with fed-batch S-SSF method in the industrialization of bioethanol production from reed.

Optical vortex amplification up to the joule level using flash-lamp-pumped Nd:YAG amplifiers has been demonstrated for the first time. In experiment, vortex seed pulses were converted from a conventional $Q$ -switched Nd:YAG laser output by a spiral phase plate and amplified with two Nd:YAG amplifier stages. A maximum output energy of optical vortex up to 995 mJ has been achieved at 10 Hz in a 10-ns pulse, corresponding to an amplification factor of 295%. A maximum second-harmonic energy up to 470 mJ was generated from the amplified vortex output by using a KD*P crystal. The prospects of joule nanosecond vortex pulses generation by this approach were discussed.

We investigate the stimulated Brillouin scattering (SBS) properties of light beams carrying orbit angular momentum (OAM). The phase conjugation of light beams carrying OAM is experimentally achieved in an SBS mirror with a random phase plate. The spectrum and the pulse width compression of SBS light are measured. It is shown that the phenomena of pulse compression is observed and OAM conservation is confirmed in the SBS process. The OAM transfer from photons to phonons may find potential applications in photon-phonon conversion-based signal-processing schemes by using OAM multiplexing.

High energy nanosecond vortex beams and cylindrically polarized beams are generated in Nd:YAG amplifiers. Vortex seed beams and cylindrically polarized seed beams are converted from a conventional Nd:YAG laser by spiral phase plate and polarization converter, respectively. Maximum output energy of optical vortex up to 995 mJ and cylindrically polarized beams up to 772 mJ have been achieved at 10 Hz in a 10-ns pulse, respectively. The amplification efficiency, the beam quality and pulse width of the amplification output are studied. Both the topological charge of the vortex seed beams and polarization state of cylindrically polarized beams are confirmed to be conserved during the amplification. The generation of high energy vortex beams and cylindrically polarized beams would be beneficial to laser material processing.

Amplification of vortex beam in flash-lamp-pumped Nd:YAG amplifiers has been demonstrated. A maximum output pulse energy up to 995mJ has been achieved at 10 Hz in a 10 ns pulse, corresponding to an amplification efficiency of 295%. Second-harmonic generation of the amplified vortex output was performed using nonlinear a KD.P crystal. Maximum second-harmonic energy of 470mJ was generated. The joule nanosecond vortex pulses will be beneficial to numbers of studies including the nonlinear optics and laser ablation.

We experimentally generate a stochastic electromagnetic beam with controllable coherence, employing two crossed zero-twisted nematic liquid crystal spatial light modulators. The coherence of the stochastic electromagnetic beam can be controlled by the variation magnitude of phase modulation of the spatial light modulators. We measure the coherence properties of the beam using Young's interference experiment. The results showed that the coherence degree along two mutually perpendicular directions can be different and controlled by introducing two kinds of different phase modulation on the two spatial light modulators.

We demonstrate, to the best of our knowledge, a new kind of laser, called a partially coherent digital laser, producing nonuniformly correlated partially coherent light beams by "playing a video" inside the cavity directly. In this laser, a spatial light modulator (SLM) with dynamic phase modulation acts as a cavity mirror. The coherence degree distribution of the output beams can be controlled simply by varying the waists of the computer-generated holograms on the SLM. The experimental results show that the coherence degree between two points on the observation plane is not only dependent on the distance between them, but also on the positions that are observed across the beam.

We generate a stochastic electromagnetic beam (SEB) with complete controllable coherence, that is, the coherence degree can be controlled independently along two mutually perpendicular directions. We control the coherence of the SEB by adjusting the phase modulation magnitude applied onto two crossed phase only spatial light modulators. We measure the beam's coherence properties using Young's interference experiment, as well as the beam propagation factor. It is shown that the experimental results are consistent with our theoretical predictions.