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Manufacturing ceramic foams derived from solid waste can not only alleviate hazards to the environment, but also obtain high value-added products. The self-foaming ceramic foams were prepared by recycling fly ash (FA) and red mud (RM) as raw materials. The pore structure, physical and mechanical properties of the sintered foams subjected to different sintering schedules were investigated. The results showed that the ceramic foams performed a self-foaming procedure in the course of sintering, derived from the combustion of the organic materials and/or the decomposition of the carbonates in the studied FA and RM. The sample sintered at 675 °C for 60 min exhibited promising properties, including a bulk density of 331 kg/m³, a porosity of 83.8 %, a water absorption of 2.91 % and a compressive strength of 1.96 MPa, which has good potential application in the fields of insulation, gardening and lightweight constructions.

Hollow multishelled structures(HoMSs) Co3O4 with specially appointed shell number(double-, triple- and quadruple-) were accurately prepared by a sequential templating approach. Due to the superiorities of inimitable porous multishelled structure, triple-HoMSs Co3O4 achieved the best performance among all the samples with a specific capacitance of 1028.9 F/g at 10 mV/s and 688.2 F/g at 0.5 A/g, respectively. Furthermore, the electrode delivered a high rate performance(89.8% retention at 10 A/g) and excellent cycle stability(6.8% loss over 2000 cycles), showing a great promise for practical application in the future.

The demand for air filtration materials in recent years has been substantially increasing on a worldwide scale because people are paying extensive attention to particulate matter (PM) pollution. In this work, we report a type of needle-punched triboelectric air filter (N-TAF) consisting of polytetrafluoroethylene (PTFE) fibers modified by silica nanoparticles and polyphenylene sulfide (PPS) fibers. Compared to conventional electrostatic precipitators, the N-TAF can be charged online by a unique nonwoven processing technology without additional energy consumption and toxic ozone emission. Owing to the triboelectrification effect, a large number of charges were generated during the process of carding and needle-punching, resulting in an increased filtration performance. Benefiting from the addition of silica nanoparticles, the PTFE fibers are endowed with many pores and grooves and substantial surface roughness, which contributes to the enhancement of triboelectrification. As a result, the N-TAF with 2 wt % silica nanoparticles (N-TAF-2) exhibited a high removal efficiency of 89.4% for PM, which is 45% higher than unmodified N-TAF (61.8%), and a low pressure drop of 18.6 Pa. Meanwhile, the decay of the removal efficiency for N-TAF-2 remained at a low level (6.4%) for 60 days. More importantly, N-TAF-2 could realize a high efficiency of 99.7% and a low pressure drop of 55.4 Pa at a high surface density. In addition, the washed N-TAF has an excellent charge regeneration performance via air blowing or manual rubbing, thus recovering the removal efficiency easily and rapidly. Ultimately, the powerful dust holding capacity (227 g m

Rational fabrication of highly efficient and non-precious metal electrocatalysts for oxygen evolution reaction (OER) are of great importance for renewable energy exploitation to solving the energy crisis and environmental problems. In this paper, we report a novel hybrid nanostructure with Co, Ni and S co-doped N-enriched porous carbon polyhedron (CoNixSy/NCP) via a absorption-pyrolysis-sulfuration strategy derived from zeolitic imidazolate framework-67 (ZIF-67) and explored its electrocatalytic performance for OER. During the synthesis process, Ni2+ is abosrbed within the pores or surface of ZIF-67 and Ni/ZIF-67 can be transformed into the Co and Ni co-doped porous carbon frameworks when it is sulfurazed at 800 °C. NiS2 and NiCo2S4 nanoparticles formed at high temperature are homogeneously dispersed in porous carbon and can activate its electrocatalytic performance. The porous carbon can enhance the electrochemical surface area and charge transfer efficiency. Benefiting from the synergistic effects between highly active NiS2, NiCo2S4, and porous carbon, CoNixSy/NCP electrocatalyst exhibits excellent electrocatalytic performance. The results show that CoNixSy/NCP also exhibits a potential as low as 1.51 V to achieve 10 mA/cm2 current density and extremely stability towards OER. The good electrocatalytic activity of CoNixSy/NCP further suggest its great potential as an efficient eletctocatalyst for sustainable energy applications.

Bone defects remain a challenging problem for doctors and patients in clinical practice. Processed pyritum is a traditional Chinese medicine that is often used to clinically treat bone fractures. It contains mainly Fe, Zn, Cu, Mn, and other elements. In this study, we added the extract of processed pyritum to β-tricalcium phosphate and produced a porous composite TPP (TCP/processed pyritum) scaffold using digital light processing (DLP) 3D printing technology. Scanning electron microscopy (SEM) analysis revealed that TPP scaffolds contained interconnected pore structures. When compared with TCP scaffolds (1.35 ± 0.15 MPa), TPP scaffolds (5.50 ± 0.24 MPa) have stronger mechanical strength and can effectively induce osteoblast proliferation, differentiation, and mineralization in vitro. Meanwhile, the in vivo study showed that the TPP scaffold had better osteogenic capacity than the TCP scaffold. Furthermore, the TPP scaffold had good biosafety after implantation. In summary, the TPP scaffold is a promising biomaterial for the clinical treatment of bone defects.

Highlights A ginsenoside Rh2-based multifunctional liposome system (Rh2-lipo) was innovatively developed.Rh2-lipo not only innovatively challenges the position of cholesterol as a liposome component, but also provides another innovative potential system with multiple functions for anti-cancer drug delivery. Electronic supplementary material The online version of this article (10.1007/s40820-020-00472-8) contains supplementary material, which is available to authorized users., Liposomes hold great potential in anti-cancer drug delivery and the targeting treatment of tumors. However, the clinical therapeutic efficacy of liposomes is still limited by the complexity of tumor microenvironment (TME) and the insufficient accumulation in tumor sites. Meanwhile, the application of cholesterol and polyethylene glycol (PEG), which are usually used to prolong the blood circulation and stabilize the structure of liposomes respectively, has been questioned due to various disadvantages. Herein, we developed a ginsenoside Rh2-based multifunctional liposome system (Rh2-lipo) to effectively address these challenges once for all. Different with the conventional ‘wooden’ liposomes, Rh2-lipo is a much more brilliant carrier with multiple functions. In Rh2-lipo, both cholesterol and PEG were substituted by Rh2, which works as membrane stabilizer, long-circulating stealther, active targeting ligand, and chemotherapy adjuvant at the same time. Firstly, Rh2 could keep the stability of liposomes and avoid the shortcomings caused by cholesterol. Secondly, Rh2-lipo showed a specifically prolonged circulation behavior in the blood. Thirdly, the accumulation of the liposomes in the tumor was significantly enhanced by the interaction of glucose transporter of tumor cells with Rh2. Fourth, Rh2-lipo could remodel the structure and reverse the immunosuppressive environment in TME. When tested in a 4T1 breast carcinoma xenograft model, the paclitaxel-loaded Rh2-lipo realized high efficient tumor growth suppression. Therefore, Rh2-lipo not only innovatively challenges the position of cholesterol as a liposome component, but also provides another innovative potential system with multiple functions for anti-cancer drug delivery. Electronic supplementary material The online version of this article (10.1007/s40820-020-00472-8) contains supplementary material, which is available to authorized users.

To explain the relationship between the hydration activity of high-titanium slag and its microstructure, the hydration activity of high-titanium slag was determined, then the mineral phase and microstructure characteristics of high-titanium slag glass phase and blast furnace slag were investigated using a series of analytical methods, which contain X-Ray Diffraction (XRD), Scanning Electronic Microscope (SEM), Fourier Transform Infrared spectroscopy (FTIR), Raman spectroscopy, and Nuclear Magnetic Resonance spectroscopy (NMR). The results showed that in slow-cooled high-titanium slag, the hydration inert mineral content was about 98%, and the glass phase content was less than 2%, hence, the hydration activity of slow-cooled high titanium slag accounted for less than 25% of that of the blast furnace slag. The content of the glass phase in water-quenched high-titanium slag was 98%, but the microstructure of the glass phase was very different from that of the blast furnace slag. The glass phase of high-titanium slag has stable forms, which are TiO44&minus, monomers, chain or sheet units O&ndash, Ti&ndash, O, and a small amount of 6-coordination Ti4+. The Ti makes the SiO4 tetrahedron in a glass phase network not only a monosilicate, but more stable forms of disilicates and chain middle groups also appeared. The relative bridge oxygen number increased to 0.2, hence, the hydration activity of water-quenched high-titanium slag took up less than 37% of that of the blast furnace slag.

The variations on physical properties and microstructures of soils are essential to explore the freeze-thaw mechanisms. We do some experiments on freeze-thaw test of Qinghai-Tibet silty clay and cryo-scanning electron microscope (cryo-SEM) observing after freeze-thaw test and monitoring the changes of temperature, pore water pressure, and displacement. The results showed that the change of pore water pressure was closely related to soil particles rearrange, particle size redistributing, and then develop a new arranging tendency of soil pores during freeze-thaw cycles. During the period of soil freezing, the pore water pressure decreased gradually, and the particles became more gathering from point to point (P–P) form along with freezing rate decreasing, the relevant microstructures had changed from the matrix structure to gel structure, and pores became more simplex. During soil melting, the pore water pressure rose to stability, and the soil mainly experienced a consolidation process. In our study, we also quantify cryo-SEM images by Image-pro Plus (IPP) software. The results reflect the change of pore water pressure had a certain correlation with structural parameters under freeze-thaw cycles. These findings substantially contribute to understand the freeze-thaw mechanism and assist in upscale the microscale physical characteristic of frozen soil.

The catalytic reaction occupies an important position in the petroleum and chemical industry, and the traditional metal-based catalytic materials are hindered because of the limited reserves, poor stability, environmental pollution and so on. In recent years, with the promotion of green chemistry and sustainable chemical, metal-free carbon based nanomaterials and their applications in catalysts have attracted wide attention, and it has become a hot topic in the fields of energy, materials and chemical industry. In this paper, the relationship between the structure and catalysis of carbon-based nanomaterials is briefly introduced. When metal free carbon based materials directly used as catalysts, their catalytic active sites are mainly contain three types. Firstly, edge atoms and defect sites, whose carbon atoms are unsaturated and have high catalytic activity, can activate oxygen molecules and catalyze methane cracking. Secondly, functional groups on the surface of carbon materials. Different functional groups can catalyze different reaction systems. The oxygen-containing functional groups, for example, have certain weak acidity and they generally possess excellent catalytic performance in the acid-base reaction and multiple oxidation reactions. Thirdly, heteroatoms that replace carbon atoms into sp2 lattices will results in the changing of electron density distribution in carbon structure, which can promotion of chemical reactions by reducing the reaction energy barriers. The progress in the basic research on the application of metal-free carbon-based nanomaterials for the reaction of liquid phase, gas phase and photoelectricity in the last five years is reviewed. By in situ infrared characterization technique ( in situ FTIR) and density functional theory (DFT) calculations, the catalytic mechanism catalyzed by carbon materials was studied and the result indicates that most of the catalytic reactions are surface reactions, whose reaction rate are greatly affected by the specific surface area. The merit and demerit including, but not limited to catalytic efficient and stability of powder catalyst and monolith catalyst are list. Specially, our study shows that the construction of three-dimensional structured monolithic carbon-based catalytic materials can effectively avoid the separation problem of powder metal free carbon-based catalytic materials, and provides a reference for solving the practical bottleneck of metal free carbon-based catalytic materials in liquid phase catalytic reaction. In addition, based on the research basis of our group, the problems and future prospect of carbon-based nanomaterials are discussed from the aspect of the reaction engineering. Actually, there are few studies on the reaction engineering of metal free carbon based catalysts. At present, metal free carbon-based catalysts are mainly used in the form of ultra-fine powders. From the perspective of chemical magnification, carbon nanomaterials participate in catalytic reactions mostly in heterogeneous catalytic process, and their catalytic performance is obviously affected by catalyst dispersion, fluidity, mixed mass transfer and so on. Conventional reactors have some problems, such as weak mixing effect, blind zone of mixing, and poor inter-phase transfer effect, which lead to the contradiction between selectivity and reaction rate in the development of industrial catalytic technology of carbon nanomaterials. At the same time, there are still some problems in the traditional catalytic process, such as poor catalyst stability, easy agglomeration, and low recycling efficiency. Therefore, in order to realize the industrial scale application of metal free carbon nanomaterials catalytic reaction system, the research and development of industrial reactor suitable for the catalytic reaction process of carbon nanomaterials and its matching process is the key to form practical technology. Three-dimensional monolithic catalyst can effectively improve the efficiency of heat and mass transfer. It is expected to solve the problems of low efficiency of separation and process transfer of metal free carbon-based catalytic materials, simplify the process flow and avoid the loss of catalyst. Therefore, there is still a long way to go for the research and application of three-dimensional metal free carbon based catalysts in the future.

A Ca5Ni4(VO4)6 low loss microwave dielectric ceramic with A site deficient garnet structure was prepared via the conventional solid state reaction method. Ca5Ni4(VO4)6 sintered at 980 °C for 4 h to a relative density of 96.2% exhibits favorable microwave dielectric properties such as a permittivity of 10.9, a Q×f value of 96,500 GHz, and a τf value of −63.6 ppm/°C. Its large negative τf could be compensated by forming a solid solution with LiCa2Mg2V3O12, that led to improved properties with a near-zero τf=−3.7 ppm/°C, er=10.2, Q×f=59,300 GHz for 0.8Ca5Ni4(VO4)6−0.2LiCa2Mg2V3O12 after sintering at 955 °C for 4 h. Further on, 0.8Ca5Ni4(VO4)6−0.2LiCa2Mg2V3O12 proved to be chemically compatible with Ag electrodes, so it might be a possible candidate for LTCC applications.

This paper presents the study on the properties of high-ductility fiber reinforced concrete made with desert sand from China&rsquo, s Mu Us desert. The workability and uniaxial tensile/compression properties of undisturbed desert sand-based fiber reinforced concrete (DS-FRC) with the change of water-to-binder ratio (W/B), sand-to-binder ratio (S/B) and desert sand replacement rate (DSRR) were experimentally investigated. Experimental results reveal that the appropriate W/B and desert sand content are conducive to the workability development of DS-FRC. The uniaxial tension/compression properties of DS-FRC are mainly affected by the W/B. Especially, the highest uniaxial tensile/compression stresses and corresponding strains are obtained at the W/B of 0.29. The S/B has similar effects on the uniaxial tensile/compression properties, and an S/B of 0.36 is the optimal ratio. In terms of the DSRR, it shows less effect on the uniaxial tensile/compression properties, even for the DSRR of 100%. The results of the tests indicate that undisturbed desert sand can be used as silica sand in high-ductility fiber reinforced concrete.

Powerful terahertz (THz) radiation sources are crucial to the development of THz science. High-energy strong-field THz pulses have many significant applications such as in the ultrafast control of matter and the THz-driven electron acceleration. In recent years, ultraintense laser-plasma interactions have been proposed as a novel approach to strong-field THz generation. In this paper, the experimental results are presented about the generation of THz radiation from a solid foil irradiated by a 10-TW femtosecond laser pulse. The THz energy as a function of laser energy and defocusing amount is studied. It is found that both the THz energy and the laser-to-THz conversion efficiency increase nonlinearly with the laser energy increasing. At maximum laser energy ~270 mJ, the measured THz pulse energy is 458 μJ, corresponding to a laser-to-THz energy conversion efficiency of 0.17%. No indication of saturation is observed in the experiment, implying that a stronger THz radiation could be achieved with higher laser energy. By simultaneously monitoring the backward scattered laser light spectrum, it is qualitatively understood that the observed THz radiation as a function of laser energy and laser defocusing distance is closely related to the electron heating mechanisms at different laser intensities. The THz spectrum and polarization are characterized by using different band-pass filers and a wire-grid polarizer, respectively. The THz radiation covers an ultrabroad band ranging from 0.2 THz to 30 THz, and shows a radially polarized distribution. By fitting the measured THz spectrum with the theory of coherent transition radiation, the THz pulse duration is inferred to be about 30 fs. At the THz focal spot of ~1 mm in size, the THz field strength is evaluated to be 3.68 GV/m. Such a strong-field THz source will enable the study of extreme THz-matter interactions.

The influence of Cr addition (0.13 wt%, 0.65 wt% and 1.07 wt%) on the microstructure, phase structure and electrochemical behavior of high strength low-alloy (HSLA) steel was investigated. The surface morphologies of HSLA steels were examined by Optical microscopy (OM) and Scanning electron microscopy (SEM). The phase structure was analyzed by x-ray diffraction (XRD). Electrochemical tests were used to study the corrosion behavior of high strength steel in 3.5 wt% NaCl solution. The results showed that the appropriate addition of Cr (1.07 wt%) alloying significantly refined grain, improved the electrochemical property and microstructure. The microstructure of all samples were the typical bcc (α) phase and the peaks including (110), (200), (211) and (220) got stronger with the increase of Cr content. Meanwhile, the T3 steel with 1.07 wt% Cr showed the best electrochemical reaction inhibition and corrosion resistance because of the highest Rt. And the corrosion morphology was from serious intergranular corrosion and pitting corrosion to slight localized corrosion with the increase of Cr contents.

采用离子注入方法在氢化物气相外延法生长的AlN薄膜中注入了不同剂量的Dy3+和Eu3+，制备了Dy3+单掺、Dy3+和Eu3+共掺的AlN样品.对于Dy3+单掺杂AlN样品，X射线衍射和拉曼散射实验结果表明随着Dy注入剂量的增加，样品的压应力也增加，形成了比较明显的损伤层；但当注入剂量由5×1014 at/cm2增加至1×1015 at/cm2时，压应力增加不明显，接近于饱和.对于Dy3+和Eu3+共掺的AlN样品，阴极荧光实验表明，AlN中Eu3+和Dy3+之间可能存在能量传递，能量传递途径为在声子辅助下从Dy3+的4F9/2→6H15/2至Eu3+的7F0→5D2的共振能量传递.此外，计算发现改变Dy3+和Eu3+离子的注入剂量比能实现发光色度坐标和色温的有效调控.

Sm(OH)3–ZnO composites were successfully synthesized by a facile hydrothermal method with Sm(NO3)3·6H2O and Zn(NO3)2·6H2O as raw materials. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The photocatalytic activity of the Sm(OH)3–ZnO composites was evaluated by the degradation of Rhodamine B (RhB) solution under Ultra Violet (UV) light and visible-light irradiation. Results show that the as-prepared Sm(OH)3–ZnO composites with self-assembled structure are well crystallized. Compared with the ZnO and Sm(OH)3 samples, the Sm(OH)3–ZnO composites exhibited enhanced photocatalytic activity in the decomposition of Rhodamine B (RhB). The degradation rate reached 98.8% under UV-light irradiation for just 10 min and 94.7% under visible-light irradiation for 180 min.

The use of reduced graphene oxide (rGO) as a conductive additive to enhance the discharge capacity and rate capability of Mn 2 CoO 4 electrode material is evaluated. Mn 2 CoO 4 and Mn 2 CoO 4 /rGO composites are prepared by a modified sol-gel method and a reflux technique, respectively. The structural and morphological features of the materials are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD shows spinel crystalline structure for Mn 2 CoO 4 . The Mn 2 CoO 4 calcined at 800 °C exhibits a three-dimensional space network structure and has better cyclic performance than the ones obtained at 600, 700, 750 and 850 °C. Mn 2 CoO 4 particles are anchored and dispersible on the flexible rGO for the Mn 2 CoO 4 /rGO composite. The Mn 2 CoO 4 /rGO anode shows a reversible capacity of 625 mAh/g over 50 cycles with 75.8% capacity retention of the 2 nd cycle and excellent rate capability. Its rate capability and cycle stability are much better compared with those of pure Mn 2 CoO 4 calcined at 800 °C. RGO not only works as a substrate to provide space for loading scattered grains, but also serves as conductive network to facilitate the collection and transportation of electrons during the cycling, indirectly increasing the conductivity of Mn 2 CoO 4 .

The effect of Nd doping and one-step carbon coating in Li4Ti4.95Nd0.05O12/C composite materials on the structure and electrochemical performance by modified citric acid sol–gel method was investigated. The obtained samples were characterized by X-ray diffraction, thermogravimetry and transmission electron microscopy. The specific capacities of the Li4Ti4.95Nd0.05O12/C composite at discharge rates of 0.5, 1, 2, 5, 10, 20 and 40 C are 176, 158, 147, 128, 110, 89 and 65 mAh g−1, respectively, which is larger than those of Li4Ti5O12 and Li4Ti4.95Nd0.05O12 materials at high rates. Li4Ti4.95Nd0.05O12/C also shows excellent cycling performance at high rates after 1000 cycles, which is attributed to its smaller polarization resistance and larger lithium-ion diffusion coefficient than Li4Ti4.95Nd0.05O12 material. The further electrochemical performance was also investigated using electrochemical impedance spectroscopy and cyclic voltammetry. Carbon-coated Li4Ti4.95Nd0.05O12 could be easily synthesized by the modified citric acid sol–gel method in one step. The Li4Ti4.95Nd0.05O12/C composite exhibited good rate capability and high Li-ion diffusion coefficient. The good performance may partially be derived from the symbiotic impurities such as Li2TiO3 and Li0.5Nd0.5TiO3, which is facile for Li+ diffusion and electron transport.

Morphology-controlled ZnS crystallites were successfully synthesized via a facile and efficient microwave hydrothermal method using different sulfur sources. The phase compositions, morphologies and photoluminescence properties of the samples were characterized by X-ray diffraction, scanning electron microscopy and luminescence spectrometer. Results show that the cubic sphalerite phase ZnS crystallites were prepared at thioacetamide as the sulfur source with the multistage nanospheres morphology, which exhibit good photocatalytic activities. ZnS microspheres with the compound phase of wurtzite and sphalerite were prepared at thiourea as the sulfur source, which exhibit obvious photoluminescence properties. The structures, photoluminescence and photocatalytic properties of the prepared ZnS crystallites were affected by different sulfur sources. In addition, the phase structure, size and the unique photoluminescence properties of the samples are believed to greatly affect the photocatalytic activities of the prepared ZnS crystallites.

Sm2O3 crystallites were controllably synthesized by the hydrothermal–calcination process with the assistance of different templates. The phase compositions, morphologies and optical properties of the as-prepared samples were characterized by X-ray diffraction, scanning electron microscope and ultraviolet–visible spectrophotometer. It is investigated that the influence of different templates on the structural and optical properties of Sm2O3 samples. Results showed that Sm2O3 crystallites with ribbon-like, granular and flake-like morphologies were obtained when NaNO3, trisodium citrate and polyvinyl-pyrrolidone (PVP) were used as template agents. These templates effectively controlled the microstructure and optical properties of the as-prepared samples. The monoclinic phase Sm2O3 crystallites with ribbon-like morphology were prepared by using NaNO3 as the template agent, which energy gap is only 4.827 eV.

Nano-TiO2 is selected as inorganic filler to fabricate the reduced crystalline composite polymer membrane. The porous polymer matrix employed in this study was poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membrane synthesized via non-solvent evaporate method and the electrolyte solution uptake was carried out in the glove box to avoid the moisture contamination. The effect of nano-TiO2 on the crystalline of porous polymer membrane was studied. It was found that blending with nano-TiO2 helps to reduce the crystalline of polymer membrane. Electrochemical impedance spectroscopy showed that the room temperature conductivity of PVDF-HFP/TiO2 composite-porous polymer electrolyte (CPPE) increased up to 1.5 × 10−3S/cm, and scanning electron microscope (SEM) micrographs showed that the micro-pores and nano-TiO2 particles were observed in the polymer membrane. Furthermore, the composite-porous polymer electrolyte was stable up to 4.5 V (vs. Li/Li+) and the LiFePO4/CPPE/Li coin cell showed excellent rate capability, the discharge capacity obtained at 0.1C, 0.5C, 1C, and 3C were 164, 157, 143, and 122 mAh/g, respectively. And the cell had about 6 % capacity loss when it discharged at 1C for 50 cycles.

SnO2nanocrystals were synthesized using SnCl4•5H2O and NH3•H2O as the main raw materials and distilled water as the solvent by microwave hydrothermal. Reaction temperature on the structure and photocatalytic activities of the SnO2nanocrystals by microwave hydrothermal process was studied. The phase composition, morphologies and photocatalytic activities of the product were characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), TEM (transmission electron microscope) and photochemical reaction instrument. Results show the crystalline and conglobation of the product have significant effect on its photocatalytic properties. The homogeneous low-agglomerated and well crystallined SnO2nanocrystals prepared at 180 °C has good photocatalytic activities during photocatalytic degradation of RhB process.

Li 4 Ti 5 O 12 was successfully synthesized by a modified solid-state reaction method with an in situ coating process. The powders were characterized by X-ray diffraction, BET surface area and scanning electron microscopy. Sub-micron Li 4 Ti 5 O 12 oxides, with a high phase purity and accurate stoichiometry, were obtained after calcination at 800 °C for 7 h. The pure Li 4 Ti 5 O 12 electrode material showed a much higher surface area and specific capacity than the one without the ultra-high speed nano-pulverization pretreatment process. Excellent reversible high-rate capability was achieved as 137 mAh g −1 at 10C, 107 mAh g −1 at 20C, 76 mAh g −1 at 40C. The result of the cycling performance showed high capacity retention of about 100% for all charge/discharge rates after 10 cycles. Electrochemical impedance spectra tests demonstrated that the lithium-ion diffusivity in Li 4 Ti 5 O 12 was improved significantly after the pretreatment, which indicated that the ultra-high speed nano-pulverization treated Li 4 Ti 5 O 12 with high dispersion and smooth particle surface would be a promising high-rate anode material for lithium-ion battery.

Silicon Carbide (SiC) Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) have started gaining significant importance in various application areas of power electronics. During the last decade, SiC MOSFETs count not only as potential, but more importantly as alternative to silicon counterparts for high efficiency, high switching frequencies and high temperatures applications. Various SiC MOSFET driver designs have been proposed and their advantages and disadvantages are discussed as well. However, the design of gate drivers for SiC MOSFETs is very challenging. In particular, a sophisticated driver design is not only associated with properly switching the MOSFETs and decreasing the switching power losses, but also it must comply with the electromagnetic compatibility. This paper shows an overview of gate drivers for SiC MOSFETs. In particular, the basic operating principle of each driver along with their applicability and drawbacks are presented.