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991.
Various low-dimensional nanostructures, such as nanowires, nanotubes, nanosheets, and fullerene-like nanoparticles have been selectively synthesized from rare-earth compounds (hydroxides, fluorides) based on a facile hydrothermal method. The subsequent dehydration, sulfidation, and fluoridation processes lead to the formation of rare-earth oxide, oxysulfide, and oxyhalide nanostructures, which can be functionalized further by doping with other rare-earth ions or by coating with metal nanoparticles. Owing to the interesting combination of novel nanostructures and functional compounds, these nanostructures can be expected to bring new opportunities in the vast research areas of and application in biology, catalysts, and optoelectronic devices. 相似文献
992.
Xuan Jin Shixin Song Zhe Liu Hong Wang Bao Wang Jie Guan Hao Zhang Qingyu Xu 《Advanced Optical Materials》2021,9(24):2101175
Downsides such as pollution, stability, and cost limit the further optoelectronic applications of cesium lead halide inorganic perovskite thin films, prepared using traditional liquid-phase and vapor-phase reactions. This study investigates the preparation of inorganic perovskite CsPbIxBr3−x (x = 0, 1, 2, 3) thin films based on a solid-phase reaction. Two solid-phase precursor thin films, with an appropriate thickness ratio, are deposited by pulsed laser deposition (PLD) and subsequently react under high temperature, without any by-products or gas volatilization. Relying on lower structural destruction from solution evaporation, and a reduced intermolecular distance of PLD-prepared solid-phase precursors, the inorganic perovskite photodetectors based on a solid-phase reaction demonstrate enhanced stability under ultrahigh humidity (90–95%). By altering the thickness of the two precursors, the crystal size of the inorganic perovskite thin films can be adjusted within the range from 40 to 150 nm. Reusable metallic masks can be applied on the PLD-prepared precursors to prepare high-precision inorganic perovskite arrays (9.6 µm). The results demonstrate the significance of a solid-phase reaction method in the commercial application of inorganic perovskite optoelectronic devices. 相似文献
993.
Adrin Leons Valentina Salaris Alicia Mujica-Garcia Marina P. Arrieta Daniel Lopez Marcela Lieblich Jos Maria Kenny Laura Peponi 《Molecules (Basel, Switzerland)》2021,26(16)
In this work, different poly (lactic acid) (PLA)-based nanocomposite electrospun fibers, reinforced with both organic and inorganic nanoparticles, were obtained. As organic fibers, cellulose nanocrystals, CNC, both neat and functionalized by “grafting from” reaction, chitosan and graphene were used; meanwhile, hydroxyapatite and silver nanoparticles were used as inorganic fibers. All of the nanoparticles were added at 1 wt% with respect to the PLA matrix in order to be able to compare their effect. The main aim of this work was to study the morphological, thermal and mechanical properties of the different systems, looking for differences between the effects of the addition of organic or inorganic nanoparticles. No differences were found in either the glass transition temperature or the melting temperature between the different electrospun systems. However, systems reinforced with both neat and functionalized CNC exhibited an enhanced degree of crystallinity of the electrospun fibers, by up to 12.3%. From a mechanical point of view, both organic and inorganic nanoparticles exhibited a decreased elastic modulus and tensile strength in comparison to neat electrospun PLA fibers, improving their elongation at break. Furthermore, all of the organic and inorganic reinforced systems disintegrated under composting conditions after 35 days. 相似文献
994.
Ryohei Oka Jun-ichi Koyama Takuro Morimoto Toshiyuki Masui 《Molecules (Basel, Switzerland)》2021,26(20)
La3LiMn1−xTixO7 (0 ≤ x ≤ 0.05) samples were synthesized by a solid-state reaction method, and a single-phase form was observed for the samples in the range of x ≤ 0.03. Crystal structure, optical properties, and color of the La3LiMn1−xTixO7 (0 ≤ x ≤ 0.03) samples were characterized. Strong optical absorption was observed at a wavelength between 400 and 550 nm, and a shoulder absorption peak also appeared around 690 nm in all samples; orange colors were also exhibited. Among the samples synthesized, the most brilliant orange color was obtained at La3LiMn0.97Ti0.03O7. The redness (a*) and yellowness (b*) values of this pigment were higher than those of the commercially available orange pigments. Therefore, the orange color of this pigment is brighter than those of the commercial products. Since the La3LiMn0.97Ti0.03O pigment is composed of non-toxic elements, it could be a new environmentally friendly inorganic orange pigment. 相似文献
995.
Chitosan is a kind of biodegradable natural polysaccharide, and it is a very promising adsorber material for removing metal ions from aqueous solutions. In this study, chitosan-based magnetic adsorbent CMC@Fe3O4 was synthesized by a one-step method using carboxymethyl chitosan (CMC) and ferric salts under relatively mild conditions. The Fe3O4 microspheres were formed and the core–shell structure of CMC@Fe3O4 was synthesized in the meantime, which was well characterized via SEM/TEM, XRD, VSM, FT-IR, thermo gravimetric analysis (TGA), XPS, size distribution, and zeta potential. The effects of initial arsenic concentration, pH, temperature, contact time, and ionic strength on adsorption quantity of inorganic arsenic was studied through batch adsorption experiments. The magnetic adsorbent CMC@Fe3O4 displayed satisfactory adsorption performance for arsenic in water samples, up to 20.1 mg/g. The optimal conditions of the adsorption process were pH 3.0, 30−50 °C, and a reaction time of 15 min. The adsorption process can be well described by pseudo-second-order kinetic model, suggesting that chemisorption was main rate-controlling step. The Langmuir adsorption model provided much higher correlation coefficient than that of Freundlich adsorption model, indicating that the adsorption behavior is monolayer adsorption on the surface of the magnetic adsorbents. The above results have demonstrated that chitosan-based magnetic adsorbent CMC@Fe3O4 is suitable for the removal of inorganic arsenic in water. 相似文献
996.
Eliza Matuszewska Agnieszka Klupczynska Krzysztof Macio&#x;ek Zenon J. Kokot Jan Matysiak 《Molecules (Basel, Switzerland)》2021,26(9)
Beehive products possess nutritional value and health-promoting properties and are recommended as so-called “superfoods”. However, because of their natural origin, they may contain relevant elemental contaminants. Therefore, to assess the quality of bee products, we examined concentrations of a broad range of 24 selected elements in propolis, bee pollen, and royal jelly. The quantitative analyses were performed with inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) techniques. The results of our research indicate that bee products contain essential macronutrients (i.e., K, P, and S) and micronutrients (i.e., Zn and Fe) in concentrations depending on the products’ type. However, the presence of toxic heavy metals makes it necessary to test the quality of bee products before using them as dietary supplements. Bearing in mind that bee products are highly heterogenous and, depending on the environmental factors, differ in their elemental content, it is necessary to develop standards regulating the acceptable levels of inorganic pollutants. Furthermore, since bees and their products are considered to be an effective biomonitoring tool, our results may reflect the environment’s condition in west-central Poland, affecting the health and well-being of both humans and bees. 相似文献
997.
Ning Xu Haifeng Lin Katsumi Uchiyama Jin‐Ming Lin 《Journal of separation science》2019,42(8):1593-1599
Pipes are the primary structural elements used for transporting fluid in various industries. The most common damage mechanism is corrosion, which occurs in pipes surface of turbine. The corrosive compounds for pipes are inorganic ion (Na+, Cl?, NH4+, NO3?, etc.) and grinding oil. For rapid and quantitative detection of inorganic ions on site, more reliable and reproducible analytical methods are demanded. A highly efficient solid–liquid sampling collection system is introduced in this work. Papering on the sample surface, inorganic cations and anions were simultaneously collected and analyzed by capillary electrophoresis with indirect ultraviolet detection. As a result, five cations (Na+, K+, NH4+, Ca2+, Mg2+) and three anions (Cl?, NO3?, SO42?) were completely separated. The efficiency of the sampling and ability of capillary electrophoresis analysis were presented by the determination of trace‐level (mg/m2) contaminants. The recoveries of cations and anions on the paper from metal surface were between 86.6 and 107.2%, and the relative standard deviations were less than 12.85%. 相似文献
998.
Xintong Jia Xiaoyue Yang Wei Zhao Yuanan Hu Hefa Cheng 《Journal of separation science》2019,42(18):2957-2967
Driven by the significant need for characterization of the chemical speciation of arsenic in food, this work developed a method for rapid determination of four common arsenic species, namely, arsenite, arsenate, monomethyl arsenic acid, and dimethyl arsenic acid, in vegetables using microwave‐assisted extraction, followed by detection with high‐performance liquid chromatography hyphenated to inductively coupled plasma‐mass spectrometry. Initial screening results showed that microwave‐assisted extraction using 1% HNO3 exhibited the highest overall efficiencies for all arsenic species without causing significant degradation of the organic ones. With the aid of response surface methodology, the optimum conditions established for extraction of arsenic species from vegetables were: 500 mg of freeze‐dried vegetable sample, extracted by closed vessel microwave‐assisted extraction using 10 mL of 2% v/v HNO3 at 90°C for 17 min. Application of the method in the analysis of 24 market vegetable samples indicates that the extraction efficiencies for total arsenic species were in the range of 91.4–106%. Arsenite and arsenate were found to be the predominant arsenic species in the vegetables, which suggests that vegetable consumption could be an important route of inorganic arsenic exposure for the population with a heavy vegetable diet in arsenic polluted regions. 相似文献
999.
By using solvated metal cations as structure‐directing agents, three new iodoargentates, namely, [Fe(DMSO)6][Ag6I9]?DMSO ( 1 ), [Fe(H2O)6][Ag15I18] ( 2 ) and [Cd(DMSO)6][Ag8I10] ( 3 ) (DMSO=dimethyl sulfoxide) have been solvothermally prepared and structurally characterized. The structures of compounds 1 and 2 can be described as 1D chains constructed from the linkage of [Ag6I9] and [Ag5I11] building units, respectively. For compound 3 , the [Ag10I22] building blocks are directly interconnected to form a 2D [Ag8I10] layer, which are further interconnected via intermolecular forces to generate a 3D supramolecular framework with 1D large channels occupied by [Cd(DMSO)6]2+ cations. Interestingly, compounds 1 – 3 exhibit an ion‐exchange behavior for the adsorption of a specific dye (methylene blue, MB). Moreover, photocatalytic experiments indicate that these iodoargentates can be considered as promising photocatalysts for the degradation of organic dye pollutants. 相似文献
1000.
Jinqin Tuo Prof. Yihua Zhu Ling Cheng Dr. Yuhang Li Prof. Xiaoling Yang Prof. Jianhua Shen Prof. Chunzhong Li 《ChemSusChem》2019,12(12):2644-2650
High electrochemical over-potential and low product selectivity are regarded as the main limitations of electroreduction of CO2. Here, we proposed a new strategy to synthesize metal porphyrin-hybridized porous and ultra-thin carbon nanosheets (MPPCN) by the confinement function of the layered template. The layered confinement reaction protects the coordination structure of metal and nitrogen atoms during subsequent high-temperature treatment while ensuring the formation of ultra-thin structures. This method effectively prevents the aggregation of metal atoms, so that the metal atoms exhibit a dispersed state of a single atomic level. MPPCN exhibit unexpected catalytic activity for electroreduction of CO2, and the catalytic reaction can be carried out at an over-potential of 0.39 V. The faradaic efficiency of CO can reach 95.9 % at the potential of −0.7 V versus the reversible hydrogen electrode. 相似文献