无温漂滤光片的制备方法

随着光学薄膜技术的不断发展，光学薄膜器件应用的日益广泛，光学薄膜器件的温度稳定性研究也被提到了极重要的地位。针对这一问题进行了研究，并给出了相应的解决办法。

New method for preparation of D-valine

A method for preparing D-valine from L-valine by racemization and chemical resolution is presented. The resolving reagent, D-2,3-dibenzoyl tartaric acid was obtained by hydrolyzation of D-2,3-dibenzoyl tartaric anhydride prepared by reaction of benzoyl chloride with D-tartaric acid. DL-valine was prepared by racemization of L-valine in the presence of aldehyde in a medium of acetic acid at 100 to 110°C for 3 h. In the presence of mineral acid, reaction of D-2,3-dibenzoyl tartaric acid with DL-valine formed diastreroisomeric salts at 84 to 95°C. Salt composed of D-2,3-dibenzoyl tartaric acid and D-valine precipitated when the diastreroisomeric salts mixtures were cooled to 15°C. The salt was reacted with base giving D-valine with yield of 70% to 80% and optical purity of over 98%.

Preparation of TiO_2/SiO_2 Aerogels by Non-supercritical Drying Method and Their Photocatalytic Activity for Degradation of Pyridine

TiO2/SiO2 aerogels with different molar ratio of SiO2/TiO2 were prepared via non-supercritical method using tetrabutyl titanate and silica sols as raw materials. The samples were characterized by TEM, SEM, BET, IR, XRD and so on. The results indicate that the BET surface area of TiO2/SiO2 aerogels calcined at 550℃ which consisted of anatase structure of TiO2 with narrow distribution pores of 5-25 nm is as high as 357.89 m2·g-1. For the photocatalytic degradation of pyridine, the catalytic activities of TiO2/SiO2 aerogels are much higher than that of TiO2 powder. The photocatalytic activity of TiO2/SiO2 aerogels calcined at 800℃ is the optimum. The higher the content of SiO2, the higher the photocatalytic activity of TiO2/SiO2 aerogels. The cost for preparation of the aerogels is greatly reduced by using non-supercritical drying method, and the aerogels are hopefully applied in the treatment of industrial waste water such as coking effluent treatment.

Photochemical route for preparing atomically dispersed Pd_1/TiO_2 catalysts on(001)-exposed anatase nanocrystals and P25

Atomically dispersed catalysts have shown promising prospects in catalysis studies.Among all of the developed methods for synthesizing atomically dispersed catalysts,the photochemical approach has recently aroused much attention owing to its simple procedure and mild preparation conditions involved.In the present study,we demonstrate the application of the photochemical method to synthesize atomically dispersed Pd catalysts on(001)‐exposed anatase nanocrystals and commercial TiO2(P25).The as‐prepared catalysts exhibit both high activity and stability in the hydrogenation of styrene and catalytic oxidation of CO.

Preparation and Characterization of High Purity Enriched 10B Boric Acid via Anti-Solvent Recrystallization

Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM.

Preparation of BaAl_2O_4 by microwave sintering

The desulfurater(BaAl2O4) was successfully synthesized with BaCO3 and Al(OH)3 powders as raw materials by microwave sintering method.The mass loss of raw materials and the characterization of the outcome were investigated by means of TG-DSC,XRD and optical microscopy.The reaction mechanism was discussed.The experimental results show that synthesized BaAl2O4 by microwave sintering method is feasible.Compared with conventional sintering method,microwave sintering is a better way to synthesize BaAl2O4 with advantages of low temperature sintering,short time sintering and high synthesis rate.

Pyrolysis Characteristics and Kinetics of the Preparation Process of Sludge-Based Activated Carbon by ZnCl_2 Activation Method

To obtain the pyrolysis characteristics and kinetics of preparation process of sludge-based activated carbon by ZnCl2 activation method （i.e.the pyrolysis process of the sludge with ZnCl2 activation）,the characteristic of mass loss and gas products generated during pyrolysis of the sludge with ZnCl2 activation were analyzed by thermogravimetric analysis coupled with Fourier Transform Infrared Spectroscopy （TG-FTIR）.The kinetic parameters were calculated by the Coats-Redfem method and the mechanism models were established.The role of ZnCl2 in the pyrolysis process of the sludge with ZnCl2 activation was also illustrated through the comparison of the pyrolysis characteristics and kinetics of the sludge with and without ZnCl2 activation.The results showed that the pyrolysis process of the sludge with ZnCl2 activation can be divided into four stages including the dehydration of sludge and initial depolymerization of a small portion of organics matters,the decomposition of large molecular organic matters into small molecular intermediates,the further degradation of intermediates and volatilization of ZnCl2,and the decomposition of inorganic minerals and undecomposed organic matters.CO2,CO,CH4,H2O,some aldehydes and carboxylic acids are the major pyrolysis gaseous products.The activation energies and pre-exponential factors are in the range of 28.84-206.42 kJ/mol and 9885.16-8.08× 1011 min-1,respectively.During the pyrolysis of sludge,ZnC12 not only can function as a dehydration agent and inhibit the formation of tar,but also can peptize the organic matters in the sludge,making them easier to be decomposed.

Preparation of High Purity Neodymium Oxide from Brazilian Monazite by Ion Exchange

A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao Paulo）.

Production of yellow-emitting carbon quantum dots from fullerene carbon soot

Carbon quantum dots（CQDs） have emerged as a new generation of photoluminescent nanomaterials with wide applications.Among the various synthetic routes for CQDs,the acid-refluxing method,which belongs to the group of ＂top-down＂ methods,offers the advantage of large-scale production of CQDs and uses cheap and abundantly available starting materials.In this study,we evaluated the potential of fullerene carbon soot（FCS）,a by-product obtained during the synthesis of fullerene,as the starting material for CQD production.It was found that FCS can be successfully converted to CQDs in high production yield in mixed acids,i.e.,concentrated HNO_3 and H_2SO_4,under mild conditions.The fluorescence quantum yield（0） of the as-produced CQDs is in the range of 3%-5%,which is the highest value for CQDs obtained from ＂top-down＂ methods.Importantly,the CQDs prepared by this method show emission in the yellow range of the visible light,which is advantageous for their various potential applications.Further investigations reveal that the CQDs are highly photostable over a wide pH range and show good resistance against ionic strength and long-term UV irradiation.This further expands their potential use under harsh conditions.

Preparation,characterization and photocatalytic performance of Mo-doped ZnO photocatalysts

A series of Mo-doped ZnO photocatalysts with different Mo-dopant concentrations have been prepared by a grind- ing-calcination method. The structure of these photocatalysts was characterized by a variety of methods, including N2 physical adsorption, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared （FT-IR） spectroscopy, photoluminescence （PL） emission spectroscopy, and UV-vis diffuse reflectance spectroscopy （DRS）. It was found that Mo6＋ could enter into the crystal lattice of ZnO due to the radius of MO6＋ （0.065 nm） being smaller than that of Zn2＋ （0.083 nm）. XRD results indicated that Mo6＋ suppressed the growth of ZnO crystals. The FT-IR spectroscopy results showed that the ZnO with 2 wt.% Mo-doping has a higher level of surface hydroxyl groups than pure ZnO. PL spectroscopy indicated that ZnO with 2 wt.% Mo-doping also exhibited the largest reduction in the intensity of the emission peak at 390 nm caused by the recombi- nation of photogenerated hole-electron pairs. The activities of the Mo-doped ZnO photocatalysts were investigated in the pho- tocatalytic degradation of acid orange II under UV light （2 = 365 nm） irradiation. It was found that ZnO with 2 wt.% Mo-doping showed much higher photocatalytic activity and stability than pure ZnO. The high photocatalytic performance of the Mo-doped ZnO can be attributed to a great improvement in the surface properties of ZnO, higher crystallinity and lower recombination rate of photogenerated hole-electron （e-/h＋） pairs. Moreover, the undoped Mo species may exist in the form of MoO3 and form MoO3/ZnO heterojunctions which further favors the separation of e/h＋ pairs.

Enhanced photoelectrochemical and photocatalytic activities of CdS nanowires by surface modification with MoS_2 nanosheets

Nanocomposites composed of one-dimensional（1D） CdS nanowires（NWs） and 1 T-MoS2 nanosheets have been fabricated through a two-step solvothermal process. 5 mol% of MoS2 loading results in the best optical properties,photoelectrochemical（PEC） as well as photocatalytic activities for hydrogen evolution reaction（HER）. Compared with pure CdS NWs, the optimized nanocomposite shows 5.5 times enhancement in photocurrent and 86.3 times increase for HER in the presence of glucose and lactic acid as hole scavengers.The enhanced PEC and HER activities are attributed to the intimate contact between MoS2 and CdS that efficiently enhances charge carrier separation. In addition, ultrafast transient absorption（TA） measurements have been used to probe the charge carrier dynamics and gain deeper insight into the mechanism behind the enhanced PEC and photocatalytic performance.

Ethylene glycol-mediated synthetic route for production of luminescent silicon nanorod as photodynamic therapy agent

One-dimensional silicon nanorod（Si NR） has attracted considerable interest because of its unique morphology and electronic-optical properties that render Si NRs suitable for a broad spectrum of applications, such as fieldeffect transistor, drug carrier, solar cell, nanomechanical device, and lithium-ion battery. However, studies aiming to identify a new synthetic method and apply Si NR in the biomedical field remain limited. This study is the first to use an ethylene glycol-mediated synthetic route to prepare Si NR as a multicolor fluorescent probe and a new photodynamic therapy（PDT） agent. The as-prepared Si NR demonstrates bright fluorescence, excellent storage and photostability, favorable biocompatibility, excitation-dependent emission, and measurable quantity of-1O2（0.24）. On the basis of these features,we demonstrate through in vitro studies that the Si NR can be utilized as a new nanophotosensitizer for fluorescence imaging-guided cancer treatment. Our work leads to a new production process for Si NRs that can be used not only as PDT agents for therapy of shallow tissue cancer but also as excellent, environment-friendly, and red light-induced photocatalysts for the degradation of persistent organic pollutants in the future.

Preparation of TiO_2/ITO film electrode by AP-MOCVD for photoelectrocatalytic application

Titanium dioxide （TiO2） thin films were grown onto Indium tin oxide （ITO） glass under atmospheric pressure by chemical va- por deposition （AP-MOCVD） using titanium tetraisopropoxide astitanium precursor. The as-prepared TiOe/ITO films were characterized using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray photoelectron spectroscopy （XPS） and photoelectrochemical measurements. Their photocatalytic （PC） and photoelec- trocatalytic （PEC） activities were evaluated based on the results of methyl orange dye （MO） degradation experiments in aque- ous solution. The difference between the front side （EE, electrolyte/electrode interface） and the back side （SE, sub- strate/electrode interface） illumination was evaluated in both photocurrent and MO degradation experiments. The effect of the film thickness on degradation rate by PEC under the two illumination directions was also studied. Stability of TiO2/ITO film electrode was investigated in repetitive degradation experiments. Overall, the TiO2/ITO film with thickness ranging from 321 to1440 nm deposited by MOCVD method is an effective photoelectrode for MO degradation under SE illumination in PEC reaction system.

Sequential deposition method fabricating carbonbased fully-inorganic perovskite solar cells

Hybrid organic-inorganic halide perovskite material has been considered as a potential candidate for various optoelectronic applications. However, their high sensitivity to the environment hampers the actual application.Hence the technology replacing the organic part of the hybrid solar cells needs to be developed. Herein, we fabricated fullyinorganic carbon-based perovskite CsPbBr_3 solar cells via a sequential deposition method with a power conversion efficiency of 2.53% and long-time stability over 20 d under ambient air conditions without any encapsulation. An evolution process from tetragonal CsPb_2Br_5 to CsPb_2Br_5-CsPbBr_3 composites to quasi-cubic CsPbBr_3 was found, which was investigated by scanning electron microscopy, X-ray diffraction spectra, UV-vis absorption spectra and Fourier transform infrared spectroscopy. Detailed evolution process was studied to learn more information about the formation process before10 min. Our results are helpful to the development of inorganic perovskite solar cells and the CsPb_2Br_5 based optoelectronic devices.

Hydrothermal growth of MoS_2/Co_3S_4 composites as efficient Pt-free counter electrodes for dye-sensitized solar cells

MOS2/Co3S4 composite films were prepared via a facile one-step hydrothermal method, and used as efficient and low-cost Pt-free counter electrodes （CEs） for dye-sen- sitized solar cells （DSSCs）. Characterizations revealed that Co3S4 and MoS2 were obtained simultaneously during the facile hydrothermal process. The composites afforded a promising synergistic effect on the catalyzing of triiodide reduction. Enhanced electrocatalytic performance of the resultant composite films was confirmed through cyclic voltammetry （CV） and electrochemical impedance spec- troscopy （EIS） analyses. DSSCs using MoS2/Co3S4 composite CEs outperform the devices with pristine MoS2 or Co3S4 CEs in power conversion efficiency （PCE）. Furthermore, a PCE of 6.77% is obtained for the optimized devices using MoS2/Co3S4 composite CEs measured under standard 1 sun illumination （100 mW cm-2, AM 1.5G）, which is comparable to that of the devices fabricated under the same conditions with conventional thermally deposited Pt CEs （7.14%）. The results demonstrate that MoS2/Co3S4 composites are promis- ing alternatives to Pt to be applied as CEs for DSSCs,