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The universal emphasis on the study of green nanotechnology has led to biologically harmless uses of wide-ranged nanomaterials. Nanotechnology deals with the production of nanosized particles with regular morphology and properties. Various researches have been directed on nanomaterial synthesis by physical, chemical, and biological means. Understanding the safety of both environment and in vivo, a biogenic approach particularly plant-derived synthesis is the best strategy. Silver-zinc oxide nanoparticles are most effective. Moreover, these engineered nanomaterials via morphological modifications attain improved performance in antimicrobial, biomedical, environmental, and therapeutic applications. This article evaluates manufacturing strategies for silver-zinc oxide nanoparticles via plant-derived means along with highlighting their broad range of uses in bionanotechnology.

A novel palladium-catalyzed ring-opening reaction of oxabicyclic alkenes with arylsulfonyl hydrazides was first developed. In this work, we provide an efficient one-pot reaction to afford the corre...

An efficient three-component cycloaddition of oxa(aza)bicyclic alkenes/norbornene in the presence of NaN3 and arylsulfonyl chlorides was developed, affording the corresponding aziridine products in good yields (up to 82%) with moderate to good endo/exo selectivities (up to >99:1 endo/exo). Further studies showed that the cycloaddition of oxa(aza)bicyclic alkenes in the presence of NaN3 and chloroalkanes could afford the exo-cycloadduct 1,2,3-triazolines in good to excellent yields (up to 95%). Compared with the existing methodologies, the current protocol demands very simple and mild reaction conditions and is a metal-free catalyzed reaction. In addition, a plausible mechanism for the cycloaddition reaction was also proposed.

Cs xFA1- xPbI3 single crystals are expected to provide more excitement in optoelectronic applications, including photodetector, laser, light-emitting diode, etc. Herein, we aim to gain an in-depth understanding of the growth mechanisms of perovskite single crystal with various morphologies in view of microscopic dynamics by the combination of component, structure, and solvent engineering. A sequence of Cs xFA1- xPbI3 (0 ≤ x ≤ 0.14) perovskite single crystals with a dodecahedron morphology and tunable aspect ratio can be obtained by means of a solution-processed uniform-cooling approach. The optimized Cs0.1FA0.9PbI3 single crystals prepared in γ-butyrolactone mixed with dimethyl sulfoxide are theoretically and experimentally demonstrated to have superior performances, e.g., extremely higher long-term stability, lower trap density, and higher mobility. The broadband absorption, i.e., 300-910 nm, enables its application in near-infrared detection (880 nm), and the corresponding detector demonstrates higher responsivity at different light intensities and a fast photocurrent response (τ1 = 11 μs, τ2 = 10 μs). Equally important, we also explore the application of optimized Cs0.1FA0.9PbI3 single crystals with a tunable aspect ratio in an X-ray detector and the extremely high sensitivity (2772.1 μC Gyair-1 cm-2 under a bias of 150 V) demonstrates their good potential for radiation detection.

Without any surfactant or organic solvent, a water-borne method incorporated a biphasic sol-gel process and a Pickering emulsion process was firstly applied to encapsulate lanthanide complexes. Compared with the free one, the achieved double protected lanthanide fluorescence colloidal hybrid particles with core@shells structure has a specific ClO− detection with high selectivity and sensitivity in contrast with other inorganic ions including Cu2+, Fe3+ and other strong acids. With strong oxidation characteristics, ClO− can gradually penetrate through silica shell, and quench the red fluorescence of lanthanide ions in the organosilica core. This core@shell colloidal nanoprobe exhibits an excellent sensing capacity for hypochlorite in real sample. This green environment friendly method could be easily extended to form functional hybrid particles with other types of reactive oils and nanoparticles for devising other specified fluorescent sensors.

Nitraria sibirica Pall., a typical halophyte that can survive under extreme drought conditions and in saline-alkali environments, exhibits strong salt tolerance and environmental adaptability. Understanding the mechanism of molecular and physiological metabolic response to salt stress of plant will better promote the cultivation and use of halophytes. To explore the mechanism of molecular and physiological metabolic of N. sibirica response to salt stress, two-month-old seedlings were treated with 0, 100, and 400 mM NaCl. The results showed that the differentially expressed genes between 100 and 400 mmol L−1 NaCl and unsalted treatment showed significant enrichment in GO terms such as binding, cell wall, extemal encapsulating structure, extracellular region and nucleotide binding. KEGG enrichment analysis found that NaCl treatment had a significant effect on the metabolic pathways in N. sibirica leaves, which mainly including plant-pathogen interaction, amino acid metabolism of the beta alanine, arginine, proline and glycine metabolism, carbon metabolism of glycolysis, gluconeogenesis, galactose, starch and sucrose metabolism, plant hormone signal transduction and spliceosome. Metabolomics analysis found that the differential metabolites between the unsalted treatment and the NaCl treatment are mainly amino acids (proline, aspartic acid, methionine, etc.), organic acids (oxaloacetic acid, fumaric acid, nicotinic acid, etc.) and polyhydric alcohols (inositol, ribitol, etc.), etc. KEGG annotation and enrichment analysis showed that 100 mmol L−1 NaCl treatment had a greater effect on the sulfur metabolism, cysteine and methionine metabolism in N. sibirica leaves, while various amino acid metabolism, TCA cycle, photosynthetic carbon fixation and sulfur metabolism and other metabolic pathways have been significantly affected by 400 mmol L−1 NaCl treatment. Correlation analysis of differential genes in transcriptome and differential metabolites in metabolome have found that the genes of AMY2, BAM1, GPAT3, ASP1, CML38 and RPL4 and the metabolites of L-cysteine, proline, 4-aminobutyric acid and oxaloacetate played an important role in N. sibirica salt tolerance control. This is a further improvement of the salt tolerance mechanism of N. sibirica, and it will provide a theoretical basis and technical support for treatment of saline-alkali soil and the cultivation of halophytes.

A new 1,3-dipolar cycloaddition of oxa(aza)bicyclic alkenes with nitrones has been developed. The operationally simple cycloaddition allows efficient synthesis of fused bicyclic tetrahydroisoxazoles bearing exo- and anti-five member heterocyclic rings (76–99% yields) without any catalyst and additive under mild conditions. The proposed concerted mechanism and the observed selectivity are investigated by DFT calculations of the reaction pathways. This mild and practical [3 + 2] cycloaddition provides an efficient route to access highly functionalized compounds.

In this research, two novel polysaccharides (S1 and S2) from Solanum nigrum L were extracted and purified. Then homogeneity, molecular weights, major chemical contents and monosaccharide compositions of S1 and S2 were determined. Then, the effects of S1 and S2 on human faecal microbial community and short-chain fatty acid production were investigated using an in vitro fermentation model. Results showed that S1 and S2 have different impacts on human gut microbiota in vitro. S1 selectively promoted the abundance of 9 genera and the production of propionic acid, butyric acid, isobutyric acid, valeric acid and isovaleric acid; while S2 selectively promoted the abundance of 8 genera and the production of acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid and succinic acid. Also, S1 group had higher abundance of genera Butyricimonas and Megamonas and higher levels of lactic acid than S2; while S2 group had higher abundance of Megaphaera and higher levels of butyric acid, valeric acid, isobutyric acid, isovaleric acid and succinic acid comparably. We concluded that S1 and S2 may have potential prebiotic functions.

A novel palladium-catalyzed ring-opening reaction of oxabicyclic alkenes with arylsulfonyl hydrazides was first developed. In this work, we provide an efficient one-pot reaction to afford the corresponding

Organophosphate flame retardants (OPFRs), one kind of emerging flame retardants, have received prevalent attention owing to their ubiquity in aquatic matrices and their characteristics of being refractory to biodegradation. In current research, the degradation mechanism of tris-(2-chloroisopropyl) phosphate (TCPP), one of OPFRs, and its toxicological evaluation using UV-driven hydroxyl radical oxidation were investigated. A pseudo-first order reaction was fitted with an apparent rate constant (Kobs) of 0.1328 min−1 on transformation of TCPP in the case of CH2O2 0.1 mM, pH 6.6–7.1 and 4.7 mW cm−2 UV irradiation. High resolution mass spectroscopy analyses identified nine degradation products (eg., C6H13Cl2O4P (m/z 251.0002), C9H17Cl2O5P (m/z 307.0266), C9H17Cl2O6P (m/z 323.0217), C9H18Cl3O5P (m/z 343.0033)) during transformation of TCPP. The removal efficiency dropped by inhibitory effect of natural organic matters and anions, implying that the complete mineralization of TCPP may be difficult in actual water treatment process. The toxicity assessment has shown an decrease in reactive oxygen species (ROS) and apoptosis, membrane potential (MP) elevation of Escherichia coli, and biological molecular function revision (eg., metabolism and DNA biosynthesis), indicating that toxicity of degradation products were conspicuously decreased in comparison with intact TCPP. To sum up, effective detoxification of TCPP can be realized by a UV driving radical-based oxidation, which will provide an alternative safe treatment method to control TCPP in water matrix.

In this study, Pyrus betulaefolia Bunge seedlings were used to investigate the effects of an arbuscular mycorrhiza fungus (AMF; Funneliformis mosseae) on plant-growth characteristics, root morphology, salt tolerance, and ion distribution under saline-alkaline stress. An indoor pot experiment was conducted in which seedlings were inoculated with Funneliformis mosseae under treatments of four different concentrations of Na2CO3 solution. The results show that AMF could establish symbiotic relations with the P. betulaefolia root system under Na2CO3 stress. Under the same Na2CO3 stress, AMF significantly increased the height growth and biomass accumulation of P. betulaefolia seedlings. AMF also promoted the root growth of P. betulaefolia seedlings. AMF inoculation significantly affected the absorption and distribution of K+ and Na+ in P. betulaefolia. The K/Na ratios in the roots and leaves of seedlings inoculated with AMF were higher than those of seedlings without inoculation. The results of this study show that inoculation with AMF had a positive effect on enhancing the saline-alkaline tolerance of P. betulaefolia, and root treatment of P. betulaefolia seedlings with Funneliformis mosseae has the potential for application in the development of saline-alkaline soil vegetation.

Cs

Dimension regulation and defect passivation are two key strategies for highly efficient and stable perovskite solar cell. Vapor deposition of perovskite is a toxic-solvent-free method for large-scale fabrication. However, without the assistance of solvent for crystal optimization, effective structural regulation and defect passivation become challenging. Here, detailed investigations on the structural evolution of perovskite thin film are carried out in sequential vapor deposition using mixed-vapor (R-NH3I/MAI). Correlation between electron donating ability of R-NH3I (BAI, PEAI, PMAI and ALI) molecule and the way of structural transition is established. It is found that R-NH3I with stronger electron-donating ability promoted the phase transition from three-dimensional (3D) to two-dimensional (2D) perovskite. Typically, the n value from 1 to 5 can be tuned by reaction time or component control using BAI with the strongest electron donating ability. R-NH3I with weak electron-donating ability suppresses the 3D to 2D transition, but enhances the defect passivation effect. The ALI with the weakest electron donating ability shows the best passivation effect, leading to the best device performance than that of the control 3D device, with PCE of 18.23% (0.045 cm2) and 15.48% (1 cm2) and the significantly improved stability. This study provides the evidence that the concept of Lewis acid-base reaction is applicable in vapor deposition, which provides us with the selection guide of R-NH3I molecules for structural design in vapor fabrication of perovskite thin film.

Degradation of capecitabine was conducted using electrochemical oxidation, UV/H2O2 oxidation, and ozonation. Capecitabine was efficiently degraded by three advanced oxidation processes. The degradation rates of capecitabine achieved approximately 99.0% after 4 min of ozonation, 12 min of electrochemical oxidation, and 30 min of UV/H2O2 oxidation. The mineralization rate obtained was merely 10.3% for ozonation at 60 min, compared to 91.7% for electrochemical oxidation and 55.3% for UV/H2O2 oxidation. Capecitabine was degraded by oxidation, defluorination, hydrogenation, hydrolysis, ring and bond cleavage. Thus, multiple intermediates were generated during the degradation process, such as F-, formic acid, acetic acid, oxalic acid, and other intermediate metabolites with lager molecules. A total of eighteen metabolites, except for F- and carboxylic acids, were identified by QTOF-HRMS, where six of them could only be detected by the electrochemical oxidation process, two of them were by the UV/H2O2 oxidation process, and one of them by the ozonation process. Electrochemical oxidation was the only process that could achieve over 90% removal of cytotoxicity and genotoxicity, and the metabolites were non-genotoxic after 60 min of reaction. The number of live cells decreased with the increasing reaction time in ozonation, demonstrating the higher toxicity of the intermediates in ozonation. Energy cost evaluation results suggested that the lowest energy consumption was achieved at 1.8 kWh/m3 for 90% of capecitabine degradation with the O3 dosage of 250 mg/h. Energy consumptions for 50% removal of cytotoxicity were 21.3 and 6.3 kWh/m3 in electrochemical oxidation and UV/H2O2 oxidation, respectively. The highest energy cost for 50% of genotoxicity removal was observed in electrochemical oxidation, while ozonation was identified as the most cost-effective process.

In this work, a dual-response ratiometric fluorescent probe (E)-3-(5-(2-nitrovinyl)thiophen-2-yl)-9-phenyl-9H-carbazole (NTPC) for high selectivity and sensitivity detection of ClO− and N2H4 was successfully developed. This probe NTPC showed ratiometric fluorescent response to ClO− and N2H4, which induces obvious naked-eye color changes, respectively. In addition, the NTPC for ClO− and N2H4 detection displayed low detection limits of 71.4 nM and 0.6 μM, respectively. And the sensing mechanism of NTPC with ClO− and N2H4 was well confirmed by 1H NMR and HR-MS spectra. Moreover, this novel probe was applied to monitoring and differentiating ClO− and N2H4 in living cells, and exhibits good biocompatibility and low cytotoxicity.

Using Non-invasive Micro-test Technology (NMT), the Na+, K+ and H+ flux profiles in the root meristem regions were investigated in Nitraria sibirica Pall. seedlings under different NaCl concentrations. NaCl stress increased the K+ and Na+ contents in the roots of N. sibirica seedlings. NaCl stress significantly increased the steady Na+ efflux from the N. sibirica seedling roots. Steady K+ effluxes were measured in the control roots (without NaCl) and in the roots treated with 200 mM NaCl, and no significant differences were observed between the two treatments. The steady K+ efflux from roots treated with 400 mM NaCl decreased gradually. NaCl treatment significantly increased the H+ influx. Pharmacological experiments showed that amiloride and sodium vanadate significantly inhibited the Na+ efflux and H+ influx, suggesting that the Na+ efflux was mediated by a Na+/H+ antiporter using energy provided by plasma membrane H+-ATPase. The NaCl-induced root K+ efflux was inhibited by the K+ channel inhibitor tetraethylammonium chloride (TEA), and was significantly increased by the H+-ATPase inhibitor sodium vanadate. The NaCl-induced K+ efflux was mediated by depolarization-activated outward-rectifying K+ channels and nonselective cation channels (NSCCs). Under salt stress, N. sibirica seedlings showed increased Na+ efflux due to increased plasma membrane H+-ATPase and Na+/H+ antiporter activity. High H+ pump activity not only restricts the Na+ influx through NSCCs, but also limits K+ leakage through outward-rectifying K+ channels and NSCCs, leading to maintenance of the K+/Na+ balance and higher salt tolerance.

The content of toxic trace elements is an important index to measure the quality of plastic products. For a long time, the determination of toxic trace elements is the focus of third party detection and so on. It is very important to evaluate the accuracy of detection. In this paper, a mathematical model of the uncertainty of trace elements based on regression equation, constant volume and weighing weight is established. The results show that the content of Boron and Lead in the plastic samples is (66.3 ± 5.4) mg/kg and (500 ±30) mg/kg, respectively.

Nitraria sibirica Pall., a typical halophyte of great ecological value, is widely distributed in desert, saline, and coastal saline-alkali environments. Consequently, researching the salt tolerance mechanism of N. sibirica Pall. has great significance to the cultivation and utilization of salt-tolerant plants. In this research, RNA-seq, digital gene expression (DGE), and high flux element analysis technologies were used to investigate the molecular and physiological mechanisms related to salt tolerance of N. sibirica Pall. Integrative analysis and de novo transcriptome assembly generated 137,421 unigenes. In total, 58,340 and 34,033 unigenes were annotated with gene ontology (GO) terms and mapped in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, respectively. Three differentially expressed genes (DEGs) libraries were subsequently constructed from the leaves of N. sibirica Pall. seedlings under different treatments: control (CK), light short-term salt stress (CL2), and heavy long-term salt stress (CL6). Eight hundred and twenty-six, and 224 differentially expressed genes were identified in CL2 and CL6 compared to CK, respectively. Finally, ionomic analysis of N. sibirica Pall. seedlings treated with 0, 100, 200 or 300 mM concentrations of NaCl for one day showed that the uptake and distribution of Ca, Cu, Fe, Mg and K in different organs of N. sibirica Pall. were significantly affected by salt stress. Our findings have identified potential genes involved in salt tolerance and in the reference transcriptome and have revealed the salt tolerance mechanism in N. sibirica Pall. These findings will provide further insight into the molecular and physiological mechanisms related to salt stress in N. sibirica Pall. and in other halophytes.

The aquatic environments of the Pearl River Delta (PRD) in China have been contaminated by various industrial chemicals from local industries. In this study, the spatial–temporal distribution of six priority phthalate esters (PAEs) in surface water and sediments from the PRD was investigated. The PAEs were detected with total concentrations (Σ6PAEs) ranging from 0.35 to 20.70 μg L−1 in surface water and dry weight ranging from 0.88 to 5.69 μg g−1 in sediments. The Σ6PAEs concentrations in surface water were higher in the wet season than those in the dry season, while the opposite pattern was observed in sediments. Di(2-ethylhexyl) phthalate (DEHP) was the most abundant congener, which was higher than those reported in the literature. Risk quotients for relevant aquatic organisms were obtained and showed that most of these PAEs, in particular, butyl benzyl phthalate, DEHP and di-n-octyl phthalate, have significant potential health and ecological risks for the aquatic environment studied.

By introducing different dopants into the lattice, lanthanum sulfides with higher stability were prepared via the sulfurization of lanthanum oxides using CS2 gas at 1 000 °C. The sulfurizing time of 8 hours was optimized for La/Ca=2 at 1 000 °C and its sulfurization mechanism to form CaLa2S4 was via the reaction of β-La2S3 with CaS. As the increase of the La/Ca and La/Na ratio, longer sulfurizing time was required to get cubic phase. The investigation indicates that Na+ ions were more effective to stabilize cubic structure comparing with Ca2+ ions.

To synthesize pure γ-La2S3 at lower temperature, lanthanide complex La(Et2S2CN)3·phen, containing La-S bond, was chosen as the precursors to decompose. The obtained samples were characterized by X-ray power diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) with an energy dispersive spectrometer and UV-Vis diffuse reflectance spectra. The decomposition mechanism of the lanthanide complex was studied by thermogravimetric analyses (TGA). The results show that the obtained samples are cubic phase particles with sizes among 20–50 nm and the band gap is 2.97 eV, which is bigger than that of its bulk crystal. TG/DTG results indicate that La(Et2S2CN)3·phen decomposed to γ-La2S3via La4(Et2S2CN)3 as an intermediate product.

γ-La2S3 ceramics with Bi2S3 as additives were prepared by hot-pressed sintering. The microstructures and optical properties of these ceramics were studied. When the Bi2S3 content was 0.1 wt.%, the maximum transmittance was increased from 33% to 45%. Further increase in Bi2S3 content decreased the IR transmittance. The existence of Bi phase was the main factor responsible for the difference in transmittance of the pellets with various levels of Bi2S3.

γ-La 2 S 3 nanoparticles were successfully prepared by thermal decomposition of lanthanum complex La(Et 2 S 2 CN) 3 ·phen at low temperature. The obtained sample was characterized by the X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and element analysis. The decomposition mechanism of lanthanum complex was studied by thermogravimetric analyses (TGA). The results showed that the obtained samples were cubic phase particles with uniform sizes among 10-30 nm and γ-La 2 S 3 was prepared by decomposition of La(Et 2 S 2 CN) 3 ·phen via La 4 (Et 2 S 2 CN) 3 as an intermediate product. The band gap of γ-La 2 S 3 was 2.97 eV, which was bigger than bulk crystal because of pronounced quantum confinement effect.

The Ca-doped γ-La2S3 (γ-La2S3:Ca) powders with various La/Ca ratios were prepared using the coprecipitation method. The γ-La2S3:Ca powders with a ratio of La/Ca=5 was selected for sintering in order to study the effects of hot-pressing temperature and time on the microstructure and optical properties of γ-La2S3:Ca ceramics. The results showed that 1100°C for 1 h were the optimum hot-press parameters, at which the maximum transmittance of γ-La2S3:Ca ceramics up to 40% at 13 μm was obtained.

The concentration of heavy metals (Cr, Cd, Pb, Cu, Zn, Co, Ni and Tl) in water and surface sediment were investigated in the Pearl River Estuary, China. The concentrations of heavy metals in sediment were 1000-100,000 times higher than those in water. Correlation analysis and principal component analysis found that heavy metals (Zn, Cr, Pb and Co) in water may originate from anthropogenic activities, but the heavy metals in sediment indicate that Pb was dominated by nature and Zn, Cr, Co, Cd, Cu, Tl and Ni were mostly influenced by anthropogenic pollution. Enrichment factor and accumulation index of sediment heavy metal concentrations showed that S5, S6 and S7 presented a relatively serious pollution.

Effect of annealing time at 333 K in air on the ohmic property of Au/p-CdZnTe contact was studied. Through I–V measurement, it was found that Au/p-CdZnTe had excellent ohmic property after 2 h annealing. SEM and XPS analyses showed that Au atoms diffused into CdZnTe during annealing. Diffused Au did not form any compound with any element in CdZnTe, but replaced Cd sites or occupied Cd vacancy as acceptors. Thus, the heavy p-type doping layer was formed and M-p+-p ohmic contact was obtained. At the same time, about 27.01% of Te in un-deposited CdZnTe surface layer was oxided into TeO2 during 2 h annealing.

The structural damage and defects induced by the near-infrared femtosecond pulse in ZnSe crystal were investigated by scanning electron microscope and the photoluminescence spectra, respectively. The structural damage exhibits the different morphologies with the focusing angles of laser. The induced thermal strain is estimated to be about 8.7×10 −3 . Two induced point defects, zinc vacancy and selenium-related defects can exist permanently in femtosecond-irradiated ZnSe crystal, and V Se is the main factor of influencing SA emission.

A modified chemical vapor transport method in a closed-tube system was developed to grow ZnSe single crystals from zinc–selenium–Zn(NH4)3Cl5 system, where Zn(NH4)3Cl5 served as the chemical transport agent to avoid the kinetics limitations of the congruent sublimation conditions to ZnSe crystals growth. The growth temperature of 1001–1005 °C was employed. The ZnSe crystal with a dominated (1 1 1) singular face was obtained. The structure characteristic and crystalline quality of as-grown ZnSe single crystal were investigated by several methods such as XRD, rotating orientation X-ray diffraction, double-crystal diffraction, photoluminescence spectrum and optical microscope. The infrared transmission spectra and ultraviolet absorption measurement of as-grown crystal were also reported. The microscopic observation on the surface of as-grown ZnSe crystal revealed that two-dimension dendrite crystal growth governs the crystal growth in the system. Comparing this result with the growth of ZnSe–Zn(NH4)3Cl5 system suggested that ZnSe single-crystal grown directly from two elements in one step has lower purity and quality than ZnSe crystal grown from ZnSe polycrystal source system.

The bulk ZnSe single crystal was grown from the vapor by Zn(NH 4 ) 3 Cl 5 transport from ZnSe polycrystals source, which was synthesized from commercial grade high-purity elements, selenium and zinc. The growth temperature between the source and the growing ZnSe single crystal was 898–915°C and the temperature difference of the growth tube was 14–18°C. The orange ZnSe single crystal of Φ 9×25 mm was obtained. The studies on the features and habit of the growth surface show that the growth surface of as-grown ZnSe crystal was composed of {1 1 1}and {1 0 0} faces. The crystal quality of ZnSe crystal was investigated by RO-XRD. The FWHM value of RO-XRD patterns of ZnSe (1 1 1) face is 24 s. The photoluminescence spectrum is dominated by two broad peaks located at 439 and 418 nm, respectively. The etch pit density is about (5–7)×10 4 cm −2 . The absorption edge is very sharp and is located at about 465 nm. All of the above results indicate that a ZnSe single crystal with high crystalline quality and high purity can be grown from the vapor by Zn(NH 4 ) 3 Cl 5 transport.

The ZnSe single crystal with 8×7×0.8mm in size was grown directly from commercial grade high-purity elements, zinc(6N) and selenium(5N), by the CVT method. The chemical transport agent of (NH 4 ) 3 ZnCl 5 and the growth temperature of 1001~1005° C were employed. The ZnSe crystal shows only (111) face. The FWHM value of double crystal rocking curve of as-grown ZnSe slice was 50s due to the influence of free dendrite crystal microscope on the surface of ZnSe slice, which was in good agreement with the RO-XRD FWHM value of 48sec. The photoluminescence spectrum of the as-grown ZnSe crystal consists of a DAP emission and a broad SA luminescence band. The average etch pit density was about (5~8)×10 4 cm -2 . The infrared (IR) transmission spectra and ultraviolet absorption measurement indicated that the ZnSe single crystal has good crystalline perfection and high optical quality. All the results confirmed the superiority of this CVT growth method for ZnSe single crystal.

Na-doped γ-La2S3 powders with various Na/La ratios were synthesized by the gas–solid reaction method. Then they were sintered by hot pressing to study the effects of Na+ ions on the microstructures and optical properties of γ-La2S3 ceramics. A phase analysis indicated that the least appropriate Na+ dose to stabilize γ-La2S3 was Na/La = 1 : 20. IR transmission measurements showed that the pellet with Na/La = 1 : 20 had a higher infrared transmittance than other pellets, and the maximum transmittance reached 64.5% at 13 µm, which was near the theoretical transmittance of a γ-La2S3 crystal.