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Multifunctional supramolecular nanomaterials capable of targeted and multimodal therapy hold great potential to improve the efficiency of cancer therapeutics. Herein, we report a proof-of-concept nanoplatform for effective chemophotothermal therapy via the integration of folic acid-based active targeting and supramolecular nanovalves-based passive targeting. Inspired by facile surface engineering and designable layer-by-layer assembly concept, we design and synthesize PPy@UiO-66@WP6@PEI-Fa nanoparticles (PUWPFa NPs) to achieve efficient synergistic chemophotothermal therapy, taking advantage of the desirable photothermal conversion capability of polypyrrole nanoparticles (PPy NPs) and high drug-loading capacity of hybrid scaffolds. Significantly, pillararene-based pseudorotaxanes as pH/temperature dual-responsive nanovalves allow targeted drug delivery in pathological environment with sustained release over 4 days, which is complementary to photothermal therapy, and folic acid-conjugated polyethyleneimine (PEI-Fa) at the outmost layer through electrostatic interactions is able to enhance tumor-targeting and therapeutic efficiency. Such PUWPFa NPs showed efficient synergistic chemophotothermal therapy of cervical cancer both in vitro and in vivo. The present strategy offers not only the distinctly targeted drug delivery and release, but also excellent tumor inhibition efficacy of simultaneous chemophotothermal therapy, opening a new avenue for effective cancer treatment.

The double tube structure is simulated, R32 in the inner helical corrugated tubes with vertical grooves is heated by the water flowing in the outer tube to make it boil. The influence of pipe diameter and number of vertical grooves on the performance of double tube is analyzed. The evaporation temperature of the refrigerant is 283K. The temperatures of inlet refrigerant and inlet water are 280K and 320K, respectively. The flow velocity of inlet refrigerant and inlet water are 1m/s and 5m/s, respectively. The simulation results show that, compared with the smooth pipe, when the inner pipe diameter is 3, 4, 5, 6, 7mm, the surface heat transfer coefficients of the double tube have been increased by 160%, 150%, 147%, 138%, and 130%, respective. when PEC=1.691, the performance of the inner helical corrugated tube is the best, whose inner pipe diameter is 3 mm, outer pipe diameter is 6.2 mm, number of vertical grooves is 10.

Magnetite sorbents (MS) have been widely employed for water purification; however, adsorption capacity loss frequently occurs during the formation of magnetite sorbents. In this study, we report the preparation of S-doped magnetite hollow spheres (S-doped MHS) used for the removal of UO22+ with a large adsorption capacity of 450.0 mg U per g, higher than that of pure Fe3O4. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM) were used to determine the effectiveness of the synthesis of S-doped MHS. The S-doped MHS was investigated for the adsorption of uranium(vi) from an aqueous solution. In addition, the adsorption process fits the Freundlich isotherm model and pseudo-second-order rate equation perfectly. The affinity and selectivity of S-doped MHS for uranium(vi) is significantly high. S-doped MHS can be easily separated using an external magnetic field. Moreover, S-doped MHS can be used for the adsorption of other heavy metal ions, which indicates their promising potential applications as adsorbents in aqueous solutions.

Melting experiments in a vertical square enclosure are undertaken with a solid–liquid phase-change material ( n -octadecane) dispersed with nanoparticles (Al 2 O 3 ) as the nano-phase-change-material (nano-PCM). The enclosure has a cross-section dimension of 25 by 25 mm and it was 60 mm long. The vertical side walls were differentially heated isothermally while the remaining side walls were thermally insulated. The effect of dispersing nanoparticles in the base phase change material (PCM) on the melting heat transfer characteristics in the enclosure is examined for the relevant parameters in the following ranges: the mass particle fraction of nanoparticles, ω p = 0, 5, 10 wt.%; the Rayleigh number, Ra f = 1.71 × 10 6 –5.67 × 10 7 ; the Stefan number, Ste f = 0.037–0.108; and the subcooling parameter, Sb = 0.042–0.537. The surface-averaged heat transfer results obtained during the melting experiments indicate that natural convection heat transfer into the melted region of the enclosure tends to degrade markedly with increasing mass fraction of nanoparticles dispersed in the nano-PCM, when compared with that of the base PCM.

Centimeter-sized Te:GaSe (≤10 mass%) ingots have been grown by the vertical Bridgman technique and studied to reveal the potentials for phase matching and frequency conversion. Less than 5 mass% Te-doped crystals show the hexagonal structure like e-GaSe. Te:GaSe (≤2 mass%) crystals were suitable for non-linear applications. The optimal Te-doping level between 0.1 and 0.5 mass% has been clearly observed in CO2 laser SHG experiment. The CO2 laser SHG efficiency in Te:GaSe (0.1–0.5 mass%) is ∼20 % higher than that of GaSe due to better optical quality. Phase matching conditions in Te-doped crystals have been shown to be identical with those of GaSe.

Phase matching for the second harmonic generation in GaSe nonlinear optical crystals at room temperature is investigated in details. The most reliable system of dispersion equations is identified by a comparison of the modeling results for all known systems of dispersion equations and the available experimental data on phase matching for the second harmonic generation.

The simultaneous synthesis and densification of MoSi2 starting from elemental Mo and Si was carried out through a process of field-activated pressure-assisted combustion synthesis (FAPACS). After heating up to 922°C, the synthesis reaction occurs in the mode of thermal explosion but is ceased subsequently due to a sudden shock. The product consists of MoSi2, residual Mo and amorphous Si with precipitation of very small MoSi2 primary crystals containing. There is no transition phase layer between Mo and MoSi2 as well as Si and MoSi2. This indicates that metallic Mo reacts with molten Si directly forming MoSi2 in the FAPACS process, without any intermediate reaction steps involved. The formation of MoSi2 occurs via dissolution of Mo into Si melt followed by MoSi2 precipitation from the melt.

The combustion synthesis of Mo5Si3 was carried out in a chemical furnace using 5Ti + 3Si mixtures as a chemical fuel. The synthesized single phase Mo5Si3 exhibited a spatial network microstructure and angular texture of crystals. The chemical composition and crystal morphology of intermediate phases suggest that the formation of Mo5Si3 occurs via dissolution of Mo in the Si melt followed by reactive diffusion in the supersaturated “liquid Si-Mo melt-solid Mo” system.

A relatively simple efficient electrooptically Q-switched Er:Cr:YSGG laser oscillator-amplifier system in a line has been demonstrated. A Glan-Taylor prism and a cubic LiNbO3 crystal are used as the polarizer and modulator, respectively. Using the line scheme, one can adjust the system elements easily and achieve a good Q-switched-to-free-running pulse energy ratio of 75% and an energy amplification coefficient of 1.8. As short as 80 ns of the leading edge of a stable single pulse and 132 ns in FWHM with an energy of 24.5 mJ are generated. We also investigate the effects of the pump energy and the delay time on the postlasing, the stable single-pulse operation, the prelasing, the laser buildup time, and the Q-switched pulse width. The laser system demonstrated can be used for the effective ablation of soft and hard tissues.

The technique of Second-Harmonic Generation (SHG) of CO2 laser for carbon monoxide concentration detection is investigated in this paper. A simple mechanical Q-switched CO2 laser is used in our experiment, which works at 9.586 μm. The nonlinear optical crystal used for frequency doubling is ZnGeP2. Different CO concentration detections are performed and 100ppm detectable sensitivity is obtained.

Two types of electro-optically Q-switched Er:Cr:YSGG lasers with different polarizing mechanisms have been operated. For the one Q-switching and polarizing are realized with only a LiNbO3 crystal with both ends cut at Brewster's angle and for the other they are achieved by a cubic LiNbO3 crystal and a Glan-Taylor prism, respectively. The two schemes are compared with regard to both the mechanical and laser Q-switched properties.

A five-level system to control the wavelength of the in-line amplifier by the quantum interference is proposed. It is found that the gains of the first and the second probe can be adjusted by changing the coherent field and the incoherent pumping. The new scheme may find its application in optical switch and optical communications.

We present an experimental demonstration of electromagnetically induced two-photon transparency (EITT) in room temperature rubidium vapor. The 8S(1/2) to 5P(1/2) fluorescence is used to monitor the 5S(1/2)(F = 3)to 8S(1/2)(F = 3) two-photon absorption near resonance with the intermediate state 5P(3/2). A controlling pump laser beam is employed to coherently couple the 5P(3/2) and 5D(5/2) states, thus producing tw dressed intermediate states which give rise to destructive interference in the two-photon transition. An induced two-photon transparency of about 80% has been obtained at resonance; our experimental findings are in good agreement with the general theory of Agarwal et al. (Phys. Rev. Lett., 77 (1996) 1039), when the appropriate spectroscopic parameters are used.

Centimeter-sized Er-doped single crystals were grown from the melts GaSe:Er(0.025, 0.1, 0.5, 1 and 2 at%) by modified vertical Bridgman technology. Real Er content is ascertained as 0.009, 0.019, 0.033, 0.042 and 0.048 at%, respectively. Solubility of Er in GaSe does not exceed 5 x 10(-4). Optimal doping of 0.033 at% of Er was established from SHG experiment. Improved optical quality is identified as a reason of increased nonlinearity for about 24% to that in pure GaSe. New Raman scattering band is found at 2900 cm(-1) that properly related to F-4(9/2)-> I-4(9/2) transition of Er3+ ion. (C) 2013 Elsevier B.V. All rights reserved.

Inhomogeneously broadened doped solids supporting electromagnetically induced transparency are viable materials where optically tunable photonic band gaps may be observed and results are shown for Pr:YSO and nitrogen-vacancy color center materials. Such crystals, when coherently driven by a strong pump beam in a suitably designed standing wave configuration, exhibit a tunable stop-band with rather different values of the reflectivity. The different propagating behavior is investigated and characterized for a weak probe across the gap region of the two materials.

The impact of fs and ns pulses on indium and sulfur doped gallium selenide crystals with four and five different doping concentrations, respectively, has been studied in comparison with that of undoped GaSe. The inconsistence of the visual criterion of the damage threshold determination has been demonstrated. The multiphoton absorption and thermal effect have been identified as key factors limiting fs and ns pulse pump intensities, respectively. High advantages in the limit pump intensity as up to 50% for optimally indium-doped crystal and up to 4.5 times for optimally sulfur-doped crystal have been demonstrated under fs pulses expose.

A new electron cyclotron resonance (ECR) ion source (LECR3-Lanzhou Electron Cyclotron Resonance Ion Source No. 3) has been constructed this year. The main purpose of this source is to provide highly charged ion beams for atomic physics and surface physics research. The design of this ion source is based on the IMP 14.5 GHz ECR ion source (LECR2-Lanzhou Electron Cyclotron Resonance Ion Source No. 2) with double rf heating by inserting waveguide directly and aluminum chamber. Furthermore, the volume of the plasma chamber is larger than that of LECR2 so as to increase the rf power and improve beam intensity for highly charged ions. But the hexapole field on the chamber wall is kept the same value in order to compare with the performance of LECR2. After only four days conditioning the first test results were obtained. The final result of this ion source is expected to be better than LECR2's. (C) 2002 American Institute of Physics.

Employing a coated right-angled sapphire prism as the OPO cavity mirror, AgGaS2 type-I singly resonant optical parametric oscillator was demonstrated experimentally, which was pumped by a ns 1.064 μm Nd:YAG laser. Continuously tunable 2.35 to 5.27 μm radiation without changing cavity mirrors and maximum output energy 0.58 mJ per pulse are recorded.