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This study was designed to generate the full-length transcriptome of Coilia nasus using single-molecule long read isoform sequencing (SMRT-seq) technology. RNAs of brains, ovaries, and testes of C. nasus conditioned in both seawater and freshwater except for gut which was only from the fish conditioned in freshwater, were isolated. All the RNAs were pooled together equally for SMRT sequencing. One SMRT cell produced 64.18 Gb clean data, including 765,184 circular consensus (CCS) reads and 616,126 full-length non-chimeric (FLNC) reads. Finally, 93,793 non-redundant transcripts were obtained after clustered and polished. Structural analysis of the 93,793 non-redundant transcripts predicted 8242 alternative splicing events, a total of 229,825 SSR and 72,037 complete CDS. A total of 8437 lncRNA were identified. 84,617 transcripts were annotated in NR, Swissprot, GO, COG, KOG, eggnog, Pfam and KEGG database totally. This is the first full-length transcriptome of Coilia nasus, including transcripts appeared in the case of seawater, which will facilitate exploration of genetic data and life story of Coilia nasus.

A new method of crystal deformation is presented to simultaneously improve the thermoelectric and mechanical properties of InTe; this results in the successful fabrication of a thermoelectric module with a high heat-to-power conversion efficiency.

A semiconductor oxide composite consisting of ZnO nanorods (NRs) and ZnO inverse opal (IO) was fabricated and used in the photoanode of quantum dot-sensitized solar cells (QDSSCs). Using polystyrene spheres 500, 800, 1000, and 1500 nm in diameter as the IO template, ZnO composites and corresponding QDSSCs with ZnO IOs of different pore sizes were fabricated. The oxide composite prepared with ZnO IOs of different pore sizes showed similar micro-morphologies; however, the photovoltaic performance of the QDSSCs based on these composites varied greatly. The QDSSCs based on the ZnO composite achieved high power conversion efficiencies (PCEs) of more than 6%, and the maximum PCE was 7.26% when the ZnO IO pore diameter in the composite was 800 nm. This resulted in very high PCE values for the QDSSCs using CdS/CdSe quantum dot sensitizers. With further interface modifications of NH

Background Increased levels of microRNA-574-5p (miR-574-5p) have been found to be associated with increased survival of septic patients, indicating the potential role of miR-574-5p in protecting against septic progression and complications. Acute kidney injury (AKI) is one of the most common and serious complications of sepsis. Therefore, the aim of this study was to test these hypotheses: (1) in a renal cell culture line (HK-2), upregulated expression of miR-574-5p increases, and downregulated expression of miR-574-5p decreases cell viability, and (2) serum levels of miR-574-5p from patients with sepsis and AKI are lower than those of patients with sepsis but no AKI. Methods The expression of miR-574-5p was regulated by cell transfection in HK-2 cells, and HK-2 cell viability was measured using the Cell Counting Kit-8. Serum miR-574-5p expression was analyzed using qRT-PCR. The predictive value of miR-574-5p for AKI onset was evaluated using the receiver operating characteristic curve and logistic regression analysis. Results The overexpression of miR-574-5p promoted HK-2 cell viability. Fifty-eight sepsis patients developed AKI, who had significantly lower miR-574-5p expression. miR-574-5p expression was decreased with AKI stage increase and correlated with kidney injury biomarker and had relatively high accuracy to predict AKI occurrence from sepsis patients. Conclusion Overexpression of miR-574-5p in cultured HK-2 cells increases cell viability and knocked-down expression of miR-574-5p decreases cell viability. Consistently, septic patients with AKI were found to have less upregulation of miR-574-5p expression compared to septic patients without AKI. Thus, serum miR-574-5p may provide a novel biomarker for septic AKI.

The operation of dye-sensitized solar cells and quantum dot-sensitized solar cells (QDSSCs) depends strongly on the photoanode material employed. This is addressed in the present work by developing photoanodes based on a double-layer TiO2 inverse opal material with different interconnected pore sizes in the bottom and upper layers for use in QDSSCs. The proposed photoanode material leads to better infiltration of the sensitizers and the hole transporting material through the entire depth of the TiO2 layer. Double-layer TiO2 inverse opal-based QDSSCs are demonstrated to facilitate the greater absorbance of quantum dots and obtain higher photocurrent and power conversion efficiency than QDSSCs adopting single-layer TiO2 inverse opal photoanodes. Various QDSSCs employing double-layer TiO2 inverse opal photoanodes with different pore sizes in the layers are tested. The CdS/CdSe co-sensitized solar cell adopting the optimum photoanode configuration and thickness provided the highest QDSSC conversion efficiency of 5.79%.

A ternary mixture of carbon, copper sulfide, and cobalt sulfide was used to fabricate the counter electrode (CE) in quantum-dot-sensitized solar cells (QDSSCs). The ternary-mixture-based CE achieve...

microRNAs (miRNAs) are pleiotropic players in cardiac development. Recent evidence have suggested miRNAs as promisingly therapeutic targets for cardiac regeneration. This study aimed to reveal the potential effects of miR-25 on cardiomyocytes proliferation and migration. Sprague-Dawley rats received left coronary occlusion surgery to induce an in vivo model of myocardial ischemia/reperfusion (I/R) injury. Expression changes of miR-25 and Bim were tested by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot. Besides, primary neonatal and adult cardiomyocytes were transfected by the antisense oligonucleotides or mimic specific for miR-25, and then 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Boyden chamber, and terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay were respectively used to determine cardiomyocytes growth and migration. Binding effects of miR-25 on the 3'-untranslated region (3'-UTR) of Bim was assessed by dual-luciferase reporter assay. We found that miR-25 was low expressed, whereas Bim was highly expressed in I/R injury model and hypoxia-stimulated cardiomyocytes. Downregulation of miR-25 in neonatal and adult cardiomyocytes markedly reduced cell proliferation and migration, but promoted apoptosis. Consistently, downregulation of miR-25 decreased the expression of cyclin E2, cyclin D1, and CDK4, and increased the expression of p57 (KIP2) in cardiomyocytes. We additionally found that Bim was a target of miR-25. The inhibitory effects of miR-25 downregulation on cardiomyocytes survival and migration were all significantly attenuated when Bim was silenced. To sum up, our study demonstrates that miR-25 downregulation inhibits cardiomyocytes proliferation and migration, but promotes apoptosis. The role of miR-25 in cardiomyocytes was by targeting Bim.

The beams with phase gradients along the line trajectory, i.e., with the momentum flux transverse to the optical axis were generated with the beam shaping method and applied for optical manipulations in this paper. The phase distributions of the reconstructed beam in the focal plane of the objective and the moving velocity of the trapped microparticles were experimentally investigated. The experimental results showed that the moving velocity of the trapped microparticles is linearly dependent on the phase gradient possessed by the reconstructed beam. Furthermore, a generated curve beam was used to transport microparticles quickly and automatically along the curved route to avoid an obstacle. The generation method of the beams with phase gradients is simple. The beams would have potential applications in the fields such as optical trapping and optical sorting.

The Tm3+/Ho3+-SrLaGa3O7 crystal was grown using the Czochralski (CZ) method. The absorption spectra, the fluorescence spectra around 2.0 μm and energy-transfer (ET) schemes between Tm3+ ions and Ho3+ ions has been studied. The lasing performance of Tm3+/Ho3+-SrLaGa3O7 crystal for a-cut and c-cut pumped by a fiber-coupled laser diode laser are presented in this paper. The maximum output powers of 6.15 W for a-cut crystal at 2041 nm and 2.51 W for c-cut crystal at 2044 nm have been obtained, respectively. The maximum slope efficiency in terms of absorbed pump power nearly reached 36.5% for the a-cut crystal and about 18.8% for the c-cut crystal. In addition, the width of tuning can reach about 450 nm, suggesting the potential of these crystals for ultrashort pulse generation by mode-locking.

A controllable multi-sector array beam is proposed in this Letter. The beam can be generated with the metalens phase. The intensity distribution of the beam at the focal plane is analyzed in detail. The influence of the parameters a and l on the focal field distribution is discussed. The theoretical and experimental results demonstrate that the parameter a affects the size of the beam, and the additional factor l can adjust the sub-region number of the multi-sector array beams. The beam shows potential for use in optical manipulation and image transmission.

A small, nano-sized, water-soluble polyrotaxane (PR) was synthesized using a highly efficient one-pot synthesis strategy in a homogeneous water system, formed from β-cyclodextrin-(COOH)2, poly(propylene glycol)bis(2-aminopropyl ether) (PPG, 2 kDa) and a mono-(6-azido-6-desoxy)-β-cyclodextrin stopper via room temperature click chemistry. β-cyclodextrin-(COOH)2 and PR were characterized by one- and two-dimensional NMR as well as by high resolution transmission electron microscopy (HR-TEM). The number of carboxyl groups in one PR was determined by 1H NMR. Two-dimensional diffusion-ordered NMR spectroscopy (2D DOSY) and nuclear Overhauser enhancement spectroscopy (2D NOESY) show that β-cyclodextrin-(COOH)2 and PPG successfully formed an inclusion complex. HR-TEM revealed the morphology of water-soluble PR as a spherical nanoparticle with a size of approximately 3.5 nm ± 1.5 nm. PR was labeled with rhodamine to assess its biocompatibility and cell membrane penetrability in vitro. The in vivo real-time fluorescent imaging biodistribution experiments indicated that water-soluble PR can actively target tumor sites using an enhanced permeability and retention (EPR) effect, with a significantly prolonged blood circulation time in tumor-bearing mice.

Yb3+ doped BaLaGa3O7 crystal has been successfully grown by Czochralski method. The polarized absorption spectra, the fluorescence spectra and the fluorescence decay lifetime of Yb3+:BaLaGa3O7 crystal were measured at room temperature. The spectroscopic parameters of Yb3+:BaLaGa3O7 crystal are calculated. A continuous wave output power of 1.32W was obtained with four-wavelength emission corresponding to an optical-optical slope efficiency of 55%.

Intra-cavity third harmonic generation was investigated comparatively in both single- and multi-pass operations from a side-pumped acousto-optic Q-switched Nd:YAG laser. Under the pump current of 19 A, 1.68 W and 2.2 W output power at 355 nm were obtained at 9.5 kHz in single and multi-pass THG operation respectively, with a power ratio of 76%. It clarified that the first THG process in multi-pass operation played a key role in the whole frequency-tripling process. The result provided the issue that efficient third harmonic laser could be achieved via optimizing the intra-cavity single-pass THG operation due to its high beam quality.

A multi-primary color display, such as the six-primary color format, is a solution in expanding the color gamut of a full-color flat panel display. The performance of a multi-primary color display based on organic/polymer light-emitting diodes was analyzed in this study using the fitting curves of the characteristics of devices (i.e., current density, voltage, luminance). A white emitter was introduced into a six-primary color format to form a seven-primary color format that contributes to energy saving, and the ratio of power efficiency of a seven-primary color display to that of a six-primary color display would increase from 1.027 to 1.061 by using emitting diodes with different electroluminescent efficiencies. Different color matching schemes of the seven-primary color format display were compared in a uniform color space, and the scheme of the color reproduction did not significantly affect the display performance. Although seven- and six-primary color format displays benefit a full-color display with higher quality, they are less efficient than three-primary (i.e., red (R), green (G), and blue (B), RGB) and four-primary (i.e., RGB+white, RGBW) color format displays. For the seven-primary color formats considered in this study, the advantages of white-primary-added display with efficiently developed light-emitting devices were more evident than the format without a white primary.

We demonstrate for the first time, to our certain knowledge, a dual-wavelength passively Q-switched bulk laser based on the MoS2/graphene heterojunction saturable absorber. This heterojunction is prepared though a facile hydrothermal reaction and shows an excellent saturable absorption charateristic with the modulation depth of 9.12%. A 370 ns pulse laser with single pulse energy of 0.734 μJ is achieved. The corresponding output power and repetition frequency rate are 102 mW and 138.9 kHz, respectively. The stable pulse laser operates at 1047.2 and 1049.6 nm, simultaneously. This work validates the MoS2/graphene heterojunction is a promising saturable absorber for multiwavelength near-infrared pulse lasers and it may broaden the range to choose optical modulator.

The good catalytic activity, resistance to iodine corrosion, and stability of carbon materials make them ideally suited for the fabrication of counter electrodes used in dye-sensitized solar cells (DSSCs). Different carbon materials have been used to make counter electrodes, and each has its own advantages, such as good film formation or high electric conductivity. Herein, various carbon materials were mixed and employed for preparing counter electrodes in DSSCs. Both fine film morphology and improved charge-carrier transport were obtained, and the power conversion efficiency of the DSSCs was thus increased. Accordingly, a cell efficiency of 6.29% was obtained by the DSSC with a counter electrode composed of the optimum mixture of carbon nanotubes, graphite, conductive carbon black, and graphene. Furthermore, DSSCs with a flexible counter electrode were fabricated using the optimum carbon material mixture, and the corresponding DSSCs achieved a power conversion efficiency of 4.32%.

A 2.07 at.% Sm3+-doped CaYAlO4 crystal was grown by the Czochralski method. The polarized spectra and decay curve were recorded at room temperature. The spectroscopic parameters were calculated on the basis of Judd-Ofelt theory. The absorption cross-sections at 408 nm were obtained to be 2.43 × 10−20cm2 and 4.09 × 10−20cm2 for the π and σ polarization, respectively. The main emission band, which had a fluorescence branching ratio of 45.51%, was located at 601 nm with cross-sections of 10.06 × 10−22 cm2 (π-polarization), 6.97 × 10−22 cm2 (σ-polarization). The decay lifetime of 4G5/2 multiplet was measured to be 0.83 ms. The Sm3+:CaYAlO4 crystal also has a good temperature-dependent fluorescence property. The results indicate the Sm3+:CaYAlO4 crystal may be a potential candidate of orange-yellow laser pumped directly by the GaN/InGaN laser diode.

The electronic and optical properties before and after Au decoration on (1 0 1 ¯ 4) surface of dolomite were investigated based on first principles calculations. The electronic structure analysis indicates that the band gap decreases from 4.25 eV (pristine) to 0.81 eV (1 Au decorated case), and the work functions increase from 2.41 eV to 3.53 eV. The density of states analysis revealed that the band gap decrease is mainly attributed to the Au 5d doping states in the forbidden band gap. Moreover, an additional peak located at 310 nm of polarization direction on E//c appears after Au decoration, resulting in the increased absorption intensity in the ultraviolet and visible range. By comparing the redox potential with that of different kinds of pollution gas, it can be found that the Au decorated dolomite might be a good photocatalyst for NO removal. The above results indicate that the Au decorated dolomite could be used in visible light photocatalysis or photovoltaic applications due to its semiconductor characteristics and suitable redox potentials.

We report a 2 micron passively Q-switched bulk state pulsed laser with a pulse of 430 ns based on graphene-like 2D WS2 nanosheets. To the best of our knowledge, it is the shortest pulse compared with other bulk state lasers based on WS2 saturable absorbers at this waveband. The WS2 nanosheets are prepared through a facile hydrothermal reaction. Its max output power and pulse energy are 488 mW and 5.422 μJ, respectively. The wavelength is distributed from 1934 to 1942 nm. These results reveal that WS2 is a promising nanomaterial in the fields of photonics and electronics.

Tm 3+ -, Dy 3+ -BaLaGa 3 O 7 phosphors have been synthesized by solid-phase sintering. X-ray diffraction (XRD) and photoluminescence properties of the phosphors were investigated in detail. The sample Tm 3+ and Dy 3+ ions co-doped BaLaGa 3 O 7 obtain white light emission by integrating a blue emission band located at 455 nm ( 1 D 2 → 3 F 4 ) and an orange one located at 573 nm ( 4 F 9/2 → 6 H 13/2 ) attributed to Tm 3+ and Dy 3+ ions, respectively. The study on the luminescence mechanism showed that there is the energy transfer between Tm 3+ and Dy 3+ in Tm 3+ /Dy 3+ -BaLaGa 3 O 7 phosphors.

Quantitative structure–activity relationship (QSAR) studies were performed in this work to predict the pIC50 of non-glycoside sodium-dependent glucose cotransporter-2 (SGLT2) inhibitors (46 triazole derivatives). Four descriptors were selected from the pool of DRAGON descriptors using the enhanced replacement method. Three nonlinear regression methods—multilayer perceptron neural network (MLP NN), support vector machine (SVM), and projection pursuit regression (PPR)—were then used to build the QSAR models. The performance of the obtained models was assessed through the cross-validation and external validation of the test set. PPR produced a better model than MLP NN and SVM with coefficients of determination of 0.962 and 0.871 and root mean square errors of 0.162 and 0.471 for the training and test sets, respectively. This study developed simple and efficient approaches to predict the pIC50 of triazole derivatives and provided some insights into their structural features for the development of more potential SGLT2 inhibitors.

In this letter, we describe the operation of an end-pumped acousto-optic Q-switched Nd:YLF laser. According to the theoretical analysis and calculation for Nd:YLF crystal, the thermal focal length of σ-polarized laser is positive in plane-parallel resonator, while that of π-polarized laser is negative. Hence laser operation at σ-polarized 1313 nm should be stable in plane-parallel cavity. When absorbed pump power is 12.45 W and the pulse repetition frequency is 10 kHz, 3.1 W output laser at 1313 nm is achieved. As a result, the optical–optical conversion efficiency is 25.4 % and slope efficiency is 31.2 %, respectively.

Crack-free Sr(MoO4)x(WO4)1−x (x = 0.3, 0.45, 0.7) solid solution single crystals with high optical quality and large dimensions have been successfully grown by the Czochralski method for the first time. The unit cell parameters and the density change linearly on the composition x that all obey Vegard’s law, indicating an ideal isomorphous substitution of W6+ by Mo6+. The refractive index functions and the average thermal expansion coefficients are precisely measured. As the concentration of [MoO4]2− increases, the refractive indices have a monotonous increasing trend, while the thermal expansion coefficients follow a parabolic trend. In the pontaneous Raman spectra, the double-mode behavior of v1(Ag) band has been observed. The Raman shifts at 886 and 921 cm−1 with narrow line widths and high peak intensities indicate Sr(MoO4)0.45(WO4)0.55 crystal a potential uncontested dual-wavelength Raman gain medium.

The growth, spectroscopy and lasing performance of Tm/Ho: CaYAlO 4 and Tm/Ho: CaGdAlO 4 crystals are reported. The crystal exhibited a broad emission band from 1600 nm to 2200 nm. Single- and multi-wavelength operations of Tm/Ho:CaYAlO 4 and Tm/Ho:CaGdAlO 4 lasers have been investigated in detail, respectively. The maximum output powers of 376 mW for Tm/Ho:CaGdAlO 4 crystal and 582 mW for Tm/Ho:CaYAlO 4 crystals have been obtained, respectively. Red-shift of the emission wavelengths was obviously observed with the increasing of the absorbed pump power.

We demonstrate a diode-end-pumped continuous laser operating a new wavelength at 1370 nm in Nd: YLF. It is a coherent radiation exactly lies in the absorption band of the C 70 and water vapor. A maximum output power up to 4 W is achieved at an incident pump power of 14.6 W, with a slope efficiency of 35.5%, and the optical-optical efficiency of 27.4%. The laser output power instability in half an hour is less than 3%. Calculated by experimental threshold data, the stimulated emission cross section of 1370 nm transition in Nd: YLF crystal is determined to be 0.4437×10 −20 cm 2 .

Aim: Sodium–glucose cotransporter 2 (SGLT2) is a promising target for diabetes therapy. We aimed to develop computational approaches to identify structural features for more potential SGLT2 inhibitors. Materials & methods: In this work, 46 triazole derivatives as SGLT2 inhibitors were studied using a combination of several approaches, including hologram quantitative structure–activity relationships (HQSAR), topomer comparative molecular field analysis (CoMFA), homology modeling, and molecular docking. HQSAR and topomer CoMFA were used to construct models. Molecular docking was conducted to investigate the interaction of triazole derivatives and homology modeling of SGLT2, as well as to validate the results of the HQSAR and topomer CoMFA models. Results: The most effective HQSAR and topomer CoMFA models exhibited noncross-validated correlation coefficients of 0.928 and 0.891 for the training set, respectively. External predictions were made successfully on a test set and then compared with previously reported models. The graphical results of HQSAR and topomer CoMFA were proven to be consistent with the binding mode of the inhibitors and SGLT2 from molecular docking. Conclusion: The models and docking provided important insights into the design of potent inhibitors for SGLT2.

High-quality single crystals of different Er3+ concentration doped SrGdGa3O7(SGGO) were grown successfully by the Czochralski method. The absorption, up-conversion, near-infrared and mid-infrared fluorescence spectra, as well as the fluorescence decay curves of Er:4I13/2 and 4I11/2 levels in Er:SGGO crystal were measured at room temperature. As the concentration of Er3+ ions increase, the spectra of Er:SGGO crystals show weaker near-infrared emission and stronger mid-infrared emission. The lifetime of the 4I13/2 state decreases by nearly 7times while the lifetime of the 4I11/2 state decreases by only about 1.3 times in the Er:SGGO crystals. These results indicate that the heavily Er3+ doped SGGO crystals is beneficial to improve the 2.7 μm laser.

The geometry, stability and electronic properties of hydrogenated Janus MoSSe monolayer (MoSSe-Hx) (x=0-16) were investigated by first-principles calculations. Energetically, Sets is the most favorable and stable site for H adsorption. Janus MoSSe-Hx is predicted to be stable because its formation energy is lower than graphane and H2S, and the adsorption energy is lower than H atoms adsorbed on graphene and MoS2. The analysis of the electronic density distribution and bond population also show that Janus MoSSe-Hx forms stable structure. Then, the variations of electronic structure of Janus MoSSe-Hx were investigated. With the increase of the adsorbed numbers of H atoms, the density of state (DOS) of Janus MoSSe monolayer changed. It can be found that the DOS of Janus MoSSe-H2 has additional peaks in the band gap, which are introduced from H 1s doping states. With the increase of H atoms adsorbed, there are more H 1s doping states in the band gap. Correspondingly, the band gap of the Janus MoSSe-Hx monolayer gradually decreases. The band gap of pristine Janus MoSSe is 1.47 eV, and the band gap of 2 H adsorbed on Janus MoSSe is 1.41 eV. When 16 H atoms are adsorbed on Se side of Janus MoSSe, the band gap is 0.25 eV. Also, the work function of the Janus MoSSe-Hx monolayer was observed to decrease as the number of adsorbed H atoms increased. After hydrogenation process, the Se atoms transfer electrons to H atoms and Mo atoms, Mo atoms neutralize part of electrons, which leads to the weakening of the electric field pointing outward from Mo atoms to vacuum in the Janus MoSSe. As a result, the work function of the pristine Janus MoSSe is 5.24 eV, and the work function of Janus MoSSe-Hx (x=16) decreases to 3.70 eV.

The stability and electronic structures of fluorinated Janus MoSSe (MoSSe-Fx, x = 0–16) were investigated by the first-principles method. Energetically, the Setop site of Janus MoSSe is the most favorable site for F-adsorption. Based on the adsorption, binding and formation energy analysis, it seems the fluorinated Janus MoSSe is stable. The analysis of the electronic density distribution and orbital hybrid shows that the fluorinated Janus MoSSe forms stable structure as well. Then, the electronic structure and work function change with the concentration of F atoms analyzed. With the increase of adsorbed F atoms, the bandgap of Janus MoSSe-Fx decreases from 1.456 (pristine case, [Formula: see text]) to 1.073[Formula: see text]eV (semi-fluorinated case, [Formula: see text]), and changes from direct to indirect bandgap semiconductor. It is noteworthy that there are some additional doping levels near the valence band after F adsorbed, which originated from the F 2[Formula: see text] doping states. The charge population analysis shows that electrons transfer was from Se to F atoms. It is worth noting that the charge on F atom (MoSSe-F16) is two times more than Se atoms in pristine Janus MoSSe (MoSSe-F0). As a result, the built-in electric field pointed from Mo to F atoms is enhanced, resulting in the tremendous increase of the work function for fluorinated Janus MoSSe. The work function changes from 5.22[Formula: see text]eV ([Formula: see text]) in pristine case to 8.30[Formula: see text]eV after semi-fluorinated ([Formula: see text]). Therefore, due to the adjustable work function and built-in electric field, the fluorinated Janus MoSSe monolayer shows better properties for applications in the piezoelectric device, optoelectronic device or photocatalyst.

We demonstrate a passively Q-switched Yb3+:Ca3Y2(BO3)4 solid state laser using a hydrothermal prepared MoS2 nanosheets as saturable absorber. The single pulse energy up to 0.75 μJ is obtained. The corresponding shortest pulse duration and largest pulse repetition rate are 420 ns and 140.4 kHz, respectively. By using an etalon as the wavelength selection element, the output wavelength of the Q-switched pulse with a tunable range from 1030.5 to 1050.4 nm has been achieved, covering a continuous tuning range of about 20 nm. Our experimental results suggest that MoS2 saturable absorber shows great potential as a broadband passive Q-switcher for solid state wavelength tunable lasers at 1.0 μm.

The 5 at.% Yb 3+ :Na 2 Gd 4 (MoO 4 ) 7 crystal has been grown by the Czochralski method. The polarized spectra and laser parameters, including absorption cross-section, emission cross-section and gain cross-section are reported. The strong absorption peak of both σ -polarization and π -polarization spectra is centered at 976 nm, which is beneficial for the AlGaAs LD pumping. Both have the FWHM of 58 nm and their absorption coefficients are 4.03 cm −1 and 5.69 cm −1 , respectively. The emission cross-section is 2.1 × 10 −20 cm 2 at 1010 nm wavelength. The radiative lifetime and fluorescence decay lifetime of 2 F 5/2 – 2 F 7/2 are 498 μs and 522 μs, respectively. The gain emission cross-section is also evaluated. The research result shows that this crystal might be promising for both tunable and femtosecond laser applications.

The polarized absorption, emission spectra and decay time measurements of Pr3+-doped CaYAlO4 single crystal have been performed at room temperature. Based on the Judd–Ofelt theory, the spectroscopic parameters $$\Upomega_{t} (t = 2,4,6)$$ , radiative transition probabilities, radiative lifetimes and branching ratios were obtained. The stimulated emission cross-section, fluorescence lifetimes and the quantum efficiency of the promising laser transition were also calculated and compared with other reported crystals. The results show that Pr3+:CaYAlO4 is a promising candidate for visible solid-state laser emission.

Quantitative structure–property relationship modelling can be a valuable alternative method to replace or reduce experimental testing. In particular, some endpoints such as octanol–water (KOW) and organic carbon–water (KOC) partition coefficients of polychlorinated biphenyls (PCBs) are easier to predict and various models have been already developed. In this paper, two different methods, which are multiple linear regression based on the descriptors generated using Dragon software and hologram quantitative structure–activity relationships, were employed to predict suspended particulate matter (SPM) derived log KOC and generator column, shake flask and slow stirring method derived log KOW values of 209 PCBs. The predictive ability of the derived models was validated using a test set. The performances of all these models were compared with EPI Suite™ software. The results indicated that the proposed models were robust and satisfactory, and could provide feasible and promising tools for the rapid assessment of the SPM derived log KOC and generator column, shake flask and slow stirring method derived log KOW values of PCBs.

An attractive method of generating second-order data was developed by a dropping technique to generate pH gradient simultaneously coupled with diode-array spectrophotometer scanning. A homemade apparatus designed for the pH gradient. The method and the homemade apparatus were used to simultaneously determine malachite green (MG) and crystal violet (CV) in water samples. The absorbance–pH second-order data of MG or CV were obtained from the spectra of MG or CV in a series of pH values of HCl–KCl solution. The second-order data of mixtures containing MG and CV that coexisted with interferents were analyzed using multidimensional partial least-squares with residual bilinearization. The method and homemade apparatus were used to simultaneously determine MG and CV in fish farming water samples and in river ones with satisfactory results. The presented method and the homemade apparatus could serve as an alternative tool to handle some analysis problems.

In this paper, we reported a multiwavelength passively Q-switched Yb3+:GdAl3(BO3)4 solid-state laser with topological insulator Bi2Te3 as a saturable absorber (SA) for the first time, to the best of our knowledge. Bi2Te3 nanosheets were prepared by the facile solvothermal method. The influence of three Bi2Te3 densities on the laser operation was compared. The maximum average output power was up to 57 mW with a pulse energy of 511.7 nJ. The shortest pulsewidth was measured to be 370 ns with 110 kHz pulse repetition rate and 40 mW average power. The laser operated at three wavelengths simultaneously at 1043.7, 1045.3, and 1046.2 nm, of which the frequency differences were within the terahertz wave band. Our work suggests that solvothermal synthesized Bi2Te3 is a promising SA for simultaneously multiwavelength laser operation.

The growth, absorption spectra, fluorescence spectra and luminescence decay curves of Tm3+-, Ho3+-BaLaGa3O7 crystals are reported. The 3F4→3H6 and 5I7→5I8 IR transitions of the Tm3+-BaLaGa3O7 and Ho3+-BaLaGa3O7 crystals are broad emission bands at about 2.0 µm; the corresponding stimulated emission cross-sections were calculated by the Fuchtbauer–Ladenburg equation, respectively. Based on the Judd–Ofelt theory, we obtained three intensity parameters and a series of spectral parameters. The energy transfer parameters between the Tm and the Ho were also calculated. These results show that these crystals are promising as tunable infrared laser crystals for the 2.0 µm regions.

The Nd3+-doped Ba3Gd2(BO3)4 crystal with high optical quality and large size is reported in this paper. The growing processes and characteristics of Nd3+:Ba3Gd2(BO3)4 crystal are discussed. The absorption and luminescence spectra of Nd3+ in Ba3Gd2(BO3)4 crystal were measured at room temperature. The luminescence decay curve in correspondence with the 4F3/2 →4I11/2 transition centered at 1062 nm was also measured. The JO intensity parameters Ωt (t = 2,4,6) were calculated to be Ω2 = 1.263, Ω4 = 2.496, Ω6 = 3.606. The radiative lifetime τr and fluorescence lifetime τf are 317.771 and 115 μs respectively, and the fluorescence quantum efficiency is 37.1%.