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Novel high-performance non-labeled fluoro-sensing micro/nano-optics require lithographically fabricable stimuli-fluorescence transductive materials well-tailored in molecular levels, towards superior processibility, stability, sensitivity, on-chip integration and portability, and real-time and in situ analysis. Here, aggregation-induced-emission fluorophores with oxetane groups (AIEoxes) and their covalently co-crosslinkable epoxy composites are customized for the fabrication of micro/nano-devices via single/multi-photon lithography. The oxetane modification increases the AIEoxe miscibility in the epoxy matrix (doping ratio up to 10 wt%), and consequently improves the as-formed devices’ quality, stability, and fluorescence intensity and sensitivity. The multi-color-AIEoxe polymeric micro/nano-devices allow fluorescence-resonance-energy-transfer among AIEoxes, which enables sensitive and specifically spectral detection of VOCs. With the micro/nano-waveguide configuration, solvent-responsive AIE fluorescence and evanescent-field/refractive-index sensing enhance the AIE-fluorescent detection of trace organic solvents in aqueous solutions (detection limit, ∼0.004% v/v, tetrahydrofuran/water) and their facile integration in functional micro/nano-systems like optofluidics.

Semiconducting polymer dots (Pdots) have attracted much attention due to their outstanding optical properties. However, the potential of Pdots in laser technology is rarely studied. Here, we first report the benzobisthiadiazole (BBT)-based Pdot as a single broadband nonlinear saturable absorber (SA) for passively Q-switched fiber lasers at 1, 1.5, and 2 μm. The Pdot-SA possesses a strong saturable absorption, a broadband nonlinear optical response, and a large modulation depth. Once the Pdot-SA is integrated into the ytterbium-, erbium-, and thulium-doped fiber laser cavities, stable Q-switched operations are observed at the central wavelengths of 1036, 1561, and 1951 nm. Our results verify that the Pdots are promising nonlinear media for Q-switched pulse generation, and highlight the potential of Pdots for relevant nonlinear optical applications.

Background: Studies indicated that air pollutions were associated with respiratory disease have with a lag exposure–response relationship, but not linear. However, few evidences in Zhengzhou, one of the most polluted cities for China.Method: Upper respiratory tract infection (URTI) outpatient visits in the hospital, meteorological parameters and air pollutions data were obtained from October 28, 2013 to May 1, 2018 and were used for evaluating the risk effects of the air pollutants with a distributed lag non-linear model (DLNM), including the stratified analysis of gender and age.Result: 475013 cases were included, with obvious seasonal fluctuations,higher in cool/cold and lower in warm. Every increase of 10μg/m3 of PM2.5, PM10, SO2, NO2 and CO showed similar impacts on URTI outpatient visits in different genders and age sub-groups,within 0 to15 days of lag. PM10, SO2 and NO2 had the strongest immediately risk at lag 0 [RRPM10: 1.0011, 95%CI (1.0002-1.0020); RRSO2: 1.0084, 95%CI (1.0039-1.0130); RRNO2: 1.0149, 95%CI: (1.0111-1.0188), respectively], while PM2.5 and CO got highest risk at lag 15 days [RRPM2.5: 1.0014, 95%CI (1.0003-1.0025); RRCO: 1.0002, 95%CI: (1.0001-1.0003), respectively]. In addition, calculating overall accumulated effects of each 10μg/m3 increase in PM10, SO2, NO2, and CO was greater in females than in males, as well as greater in the adolescents (aged 0-18 years) and elderly (aged ≥ 60 years) than in adults (aged 19-59 years), except CO was greater in the adolescents and adults than in the elderly. No significant cumulative effects were found in PM2.5. O3 levelwasno significant correlation withURTI outpatient visits throughout the lag period.Conclusions: Our results indicated that PM10, SO2, NO2 and CO had strong immediate and lag cumulative effects in the females, adolescents, and elderly. PM2.5 has lag effects but has no significant lag cumulative impact effects on gender and age.

This publisher’s note contains corrections to Opt. Lett. 45, 2580 (2020).OPLEDP0146-959210.1364/OL.391232

The stability and catalytic activity of Au10, Au13 and Au20 clusters in water gas shift (WGS) reaction were investigated by density functional theory (DFT); the adsorption behavior of reaction species and the reaction mechanism of WGS on various Aun clusters were explored. The results indicated that the stability of three Aun clusters follows the order Au10 Au10 > Au20. Three Aun clusters exhibit the same rate-determining step for WGS, i.e. H2O dissociation; however, they are quite different in the actual reaction routes. Over Au10 cluster, the WGS reaction follows the carboxyl mechanism, characterized by the direct dissociation of COOH*; over Au13 cluster, the redox mechanism applies, suggested by the disproportionation of two OH*; over Au20 cluster, the WGS reaction proceeds via the carboxyl mechanism, represented by the disproportionation of COOH* and OH*. A comparison for the optimal reaction paths over three Aun clusters suggests that the Au13 cluster has the highest catalytic activity in the WGS reaction at low temperature.

In this paper, we synthesized five different types of ZnCr layered double hydroxides with different anions (F−, Cl−, Br−, I− and NO3−). A thorough determination of the structure, chemical composition and other physical and chemical properties of the synthesized LDHs materials were done by techniques such as XRD, FTIR, BET, ICP-AES and UV–vis. The photocatalytic degradation of hexachlorobenzene reaction showed that different anions have largely influence on the reactivity and selectivity of the LDHs. The structure stability difference of the LDHs was explained and compared based on the difference of the following physical properties such as Mulliken bonding population, hydrogen bonding and density of states, which were calculated based on DFT theory. It was found that the photocatalytic performance of these LDHs was highly related to their structure stability. In addition, the HCB degradation mechanism was also analyzed by combining GC–MS data and the dissociation energy calculation.

The adsorption behavior, decarbonylation and hydrogenation reaction mechanisms of furfural on best Pd/Cu(111) bimetallic model were investigated by density functional theory method. The results show that the initial adsorption at O3-Pd-top and O7-Cu-hcp site is most stable, with the adsorption energy of 73.4 kJ/mol. On the Pd/Cu(111) bimetallic surface, decarbonylation reaction of furfural is more likely to occur. The decarbonylation reaction of furfural has low activation energy. Each steps of decarbonylation mechanism is exothermic reaction. Furfural tends to form (C4H3O)CO by losing the H atom from the branch chain, and furan is then formed by decarbonylation and hydrogenation of the intermediate. Throughout the process, the hydrogenation of C4H3O is the rate-determining step with the highest activation energy barrier of 72.6 kJ/mol. For the hydrogenation of furfural, reacting with the first hydrogen is the rate-determining step, and it has the highest reaction energy barrier of 290.4 kJ/mol.

Here a continuous axial-spiral phase microplate (CAsPP), based on combining a logarithmic axicon and a spiral phase plate, was proposed for generating high-quality higher-order Bessel vortex beams. The novel optical component implemented via femtosecond laser direct writing possesses compact geometry and unique optical properties. The CAsPP with a diameter of 80 µm possesses a controllable long focus ranging from 50 to 600 µm and exhibits a good self-healing ability after free transmission of about 45 µm. Unique optical properties were demonstrated in both experiments and simulations, which were well matched to each other. This Letter provides new opportunities for applications in integrated optics, optical trapping, laser machining, and information reconstruction.

Photodynamic therapy (PDT) is a potent treatment for clinical therapy of superficial tumors. This study describes the metallophorphyrin loaded semiconducting polymer dots (Pdots) for PDT applications. We use conjugated polymers as light-harvesting matrices and metalloporphyrin as triplet photosensitizers to prepare small nanoparticles. Energy transfer occurred from conjugated polymers to metalloporphyrin along with the quenching of polymer fluorescence and amplified singlet oxygen generation. Notably, both spectroscopy and energy level analysis indicated a triplet-triplet energy transfer mechanism in metalloporphyrin loaded Pdots yielding singlet oxygen. The singlet states of metalloporphyrin were first populated by energy transfer, and then transferred to the triplet states through efficient intersystem crossing. We postulate that energy transfer occur from the triplet states of metallophorphyrin to the triplet states of conjugated polymers, which interact with dissolved oxygen and give high singlet oxygen generation. This mechanism is different from the porphyrin-doped Pdots, which sensitize oxygen through triplet states of dyes. We evaluate the singlet oxygen yield and photodynamic effect of metalloporphyrins doped Pdots by various cellular assays. The results show that metalloporphyrins doped Pdots exhibit high singlet oxygen generation and effectively destroy cancer cells at a low nanoparticle concentration and light irradiation dose, indicating their promising application in photodynamic cancer treatment.