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This paper discusses several ways to implement quality education in mathematics teaching from the aspects of paying attention to the teaching process of knowledge occurrence, strengthening the guidance of learning method, cultivating students' spirit of conscious exploration, and improving students' mathematical quality with transforming ideas.

We demonstrate instrumentation and methods to enable fluorescence-detected photothermal infrared (F-PTIR) microscopy, then demonstrate the utility of F-PTIR to characterize the composition within phase-separated domains of model amorphous solid dispersions (ASDs) induced by water sorption. In F-PTIR, temperature-dependent changes in fluorescence quantum efficiency are shown to sensitively report on highly localized absorption of mid-infrared radiation. The spatial resolution with which infrared spectroscopy can be performed is dictated by fluorescence microscopy, rather than the infrared wavelength. Following proof of concept F-PTIR demonstration on model systems of polyethylene glycol (PEG) and silica gel, F-PTIR enabled the characterization of chemical composition within inhomogeneous ritonavir / polyvinylpyrrolidone-vinyl acetate (PVPVA) amorphous dispersions. Phase separation is implicated in the observation of critical behaviors in ASD dissolution kinetics, with the results of F-PTIR supporting the formation of phase-separated drug-rich domains upon water absorption in spin-cast films., 5 pages, 4 figures

Anode material Li2TiO3–coke was prepared and tested for lithium-ion batteries. The as-prepared material exhibits excellent cycling stability and outstanding rate performance. Charge/discharge capacities of 266 mA h g−1 at 0.100 A g−1 and 200 mA h g−1 at 1.000 A g−1 are reached for Li2TiO3–coke. A cycling life-time test shows that Li2TiO3–coke gives a specific capacity of 264 mA h g−1 at 0.300 A g−1 and a capacity retention of 92% after 1000 cycles of charge/discharge.

A series of tris(pyrazolyl)borate mono-, di- and trinuclear complexes, [Tp2Ln]nX (Ln = Eu, Tb, Gd, Dy, Xn− = various mono-, bis- and tris(β-diketonates) has been prepared. The Tb3+ and Dy3+ complexes are luminescent single molecular magnets (SMM) and exhibit luminescence quantum efficiencies up to 73% for the Tb3+ and 4.4% for the Dy3+ compounds. Similar Eu3+ complexes display bright emission only at lower temperatures. The Dy3+ and Tb3+ complexes possess SMM behavior in a non-zero dc field at low temperatures, while the polynuclear Dy3+ complexes also show slow magnetic relaxation even in zero dc field up to 8 K. Ueff-values determined from dynamic magnetic measurements were up to 31 and 6 cm−1 for the Dy3+ and Tb3+ complexes, respectively. It was found that within a series of Dy3+ and Tb3+ compounds, Ueff and luminescence quantum yields decreased with increasing nuclearity of the compounds and a shortening of the intramolecular Ln–Ln distance. ΔOrbach-values estimated from low-temperature luminescence spectra were significantly higher than those obtained from ac magnetic data, which may be due to involvement of additional processes in the relaxation mechanism (quantum tunneling, Raman, direct) reducing the energy barrier. Some of the Tb3+-compounds also display metal-centred electroluminescence, giving them potential as emitting layers in LEDs.

Rational design and fabrication of two-dimensional (2D) functional materials is of important significance in tackling fundamental issues for electrocatalysis. Here, a novel synthesis strategy is developed using basic zinc carbonate (BZC) nanosheets as 2D self-template to construct Fe-Nx active sites in porous carbon nanosheets (Fe-N-PCNS). Poly schiff base (PSB) is synthesized by in-situ polymerization reaction on the surface of BZC nanosheets, then coordinates with iron ion to obtain PSB-Fe@BZC complex. During pyrolysis, PSB-Fe@BZC complex undergoes a series process of decomposition of BZC nanosheets, reduction of zinc oxide and zinc evaporation, in which BZC nanosheets plays a decisive role in fabricating hierarchically porous carbon nanosheets with uniformly dispersed Fe-Nx active sites. As a result, Fe-N-PCNS displays an excellent electrocatalytic performance for oxygen reduction reaction with positive half-wave potential (0.91 V), large kinetic limiting current density (54.3 mA cm-2), high stability and superior methanol resistance in alkaline media, which surpasses those of Pt/C catalyst. Moreover, Fe-N-PCNS demonstrates remarkable electrocatalytic performance in primary Zn-air batteries with the outstanding discharge durability (with 18 cycles over 100 h). This self-templated strategy provides a new way for the fabrication of unique 2D carbon-based electrocatalysts.

A facile method is to prepare novel CeMoxOy-clay hybrid catalysts with layered structures by using organic cation modified clay as support. During the preparation process, cerium cations and molybdate anions are easily adsorbed and impregnated into the interlamellar space of the organoclay, and after calcination they undergo transformation to highly dispersed CeMoxOy nanoparticles within the interlamellar space of the clay. As expected, the prepared CeMo0.15Ox-OC-T catalysts with layered structures had high selective catalytic reduction (SCR) activity such as high NOx conversion of >90% in the wide temperature range of 220–420 °C. Meanwhile, they also exhibit high stability and tolerance to water vapor (5 vol%) and SO2 (200 ppm), demonstrating that these novel catalysts could serve as a good alternative for NH3-SCR in practical application.

Ultra-deep desulfurization is a major requirement for upgrading the quality of fuel and power sources for fuel-cells. A series of mesoporous TiO2–SiO2 adsorbents were prepared and investigated for ultra-deep adsorption of benzothiophene (BT) and dibenzothiophene (DBT) from model fuel at ambient conditions. The adsorbents were characterized via SEM, XRD, N2-BET, FT-IR and NH3-TPD techniques. The results revealed that the adsorbent containing 40 wt% silica achieved the desulfurization efficiency higher than 99% when the initial sulfur concentration in the model fuel was 550 ppm. The high desulfurization performance of the adsorbent was attributed to its large specific surface and surface acidity. It also achieved a high sulfur adsorption capacity of 7.1 mg g−1 in a fixed-bed test, while its static saturated sulfur capacity was 13.7 mg g−1. The order of selectivity towards the adsorption of different organic sulfurs was DBT > BT&DBT > BT. The kinetics of the adsorption of organic sulfur was studied and the results indicated that the pseudo-second order model appropriately fitted the kinetics data. Furthermore, the used adsorbent can be easily regenerated and the desulphurization efficiency of the recovered adsorbent after five regeneration cycles was still maintained at 94.5%.

Raman spectra were perturbed such that an intentional misclassification was induced when using a dimension reduction classifier such as linear discriminate analysis (LDA). These perturbations were primarily targeted at patterning the noise within the spectra such that detection is difficult to detect by visual inspection. Data-intensive decisions are increasingly important to mine the increasing volume of information accessible by modern instrumentation. These decisions are conceptually performed through projection of measurements on high dimensional manifolds to low-dimensional outcomes. This dimension reduction provides suppression of stochastic random noise to better inform the decision. However, non-stochastic patterning of the “noise” can induce intentional misclassification that is difficult to easily detect by visual inspection. Such digital attacks could result in intentional changes in decisions made from many routine automated classifiers. Preliminary results using Raman spectra showed that misclassification can be induced by picking a target classification and patterning the noise in the spectra such that in a reduced dimensional space, it is moved towards the target classification. Development of approaches for optimizing the attacks serves as a prelude for generation of robust classification strategies less susceptible to intentional attacks.

A hyperspectral beam-scanning microscope operating in the long wave infrared (LWIR) is demonstrated for future application to stand-off imaging platforms. A 32-channel quantum-cascade laser (QCL) array enables rapid wavelength modulation for fast hyperspectral imaging through sparse sampling in position and wavelength, which when coupled with image reconstruction techniques can enhance frame rate. Initial measurements of dichloromethane and water mixtures are shown, utilizing spectral information for classification across the field of view. Ongoing efforts aim to utilize copropagating visible and IR beams to enhance spatial resolution for the IR measurements by combining spatial information retrieved from visible images obtained concurrently. Future work will leverage Lissajous trajectories for sparsely-sampled beam-scanning and extend the image interpolation algorithms to arbitrary dimension for sparse sampling in the spectral domain. Simulations of the error associated with various sparse-sampling methods are also presented herein which support the use of Lissajous trajectories as a sparse-sampling method in beam-scanning microscopy.

A series of phosphorylation and blank CeSn 0.8 W 0.6 O x /TiAl 0.2 Si 0.1 O y catalysts prepared by extrusion molding were tested for NH 3 -SCR of NO, and were characterized by techniques of X-ray diffraction (XRD), Brumauer-Emmett-Teller (N 2 -BET), environmental scanning electron microscope (ESEM), temperature programmed reduction (H 2 -TPR) and temperature programmed desorption (NH 3 -TPD). Effects of phosphorylation on catalytic activity and sulfur-resisting performance of the CeSn 0.8 W 0.6 O x /TiAl 0.2 Si 0.1 O y for NH 3 -SCR of NO were mainly studied. Results showed that the phosphorylation improved the catalytic activity and sulfur-resisting performance in an active temperature window of 300–440 °C, and the phosphorylation catalyst with 0.4 wt.% H 3 PO 4 exhibited the best catalytic performance and the strongest sulfur-resisting performance. Analysis showed that the phosphorylation increased specific surface area, enhanced the surface acidity and improved redox properties.

A series of CeO2/Al2O3 and CeMoxOy/Al2O3 catalysts were prepared by an extrusion method for selective catalytic reduction of NOx, and were characterized by techniques of XRD, XPS, N2-BET, H2-TPR and NH3-TPD. Promotional effects of molybdenum additives on catalytic performances and tolerances toward SO2 and H2O poisoning of the catalysts were comparatively studied. Results showed that the CeO2/Al2O3 catalyst with the Ce/Al molar ratio of 1:5 exhibited the best catalytic performance; molybdenum additives greatly improved catalytic performance of the CeMoxOy/Al2O3 catalysts, and the catalyst with the Al/Ce/Mo molar ratio of 5:1:0.15 calcinated at 550 °C exhibited the highest catalytic activity above 95 % in active temperature window of 250–430 °C under the gas hourly space velocity (GHSV) of 7200 h−1. Moreover, molybdenum additives broadened the range of the active temperature, and significantly enhanced the anti-sulfur poisoning ability. Analysis showed that the promotional effects of molybdenum additives were attributed to the improvement of specific surface area, increment of surface acidity and the enhancement of the redox properties. The molybdenum additives significantly increase the catalytic performance of CeO2/Al2O3 for selective catalytic reduction of NOx and greatly broaden the range of the active temperature. The reasons mainly due to molybdenum additives improve the specific surface area, increase the proportion of Ce3+/(Ce4++Ce3+) and Oα/(Oα + Oβ) on the surface, and enhance the amount of the Lewis acid sites.

Titanium nitride (TiN) nanoparticles hybridized with Fe and N co-doped carbon nanosheets (Fe-N-CNS) composite is constructed by a facile in-situ self-template strategy. During the low-temperature pyrolysis process, uniformly TiO2 nanoparticles were formed and anchored into Fe-doped carbon nitride nanosheets. After further high-temperature pyrolysis, Fe-doped carbon nitride nanosheets as self-template could decompose to form Fe-N co-doped carbon nanosheets and TiO2 nanoparticles were transferred into TiN nanoparticles during the high-temperature nitriding treatment. As a result, TiN nanoparticles hybridized with Fe-N-CNS composites (TiN/Fe-N-CNS) exhibit excellent ORR activity with more positive half-wave potential (0.87 V) and large limiting current density (4.43 mA cm−2) as well as high selectivity (electron transfer number around 4) for ORR in alkaline media. Moreover, it also shows higher stability and better methanol tolerance than those of commercial Pt/C catalyst in both alkaline and acidic media. This excellent ORR performance is attributed to the enhanced specific surface area and synergistically promotion effect of uniformly dispersed TiN on Fe-N-CNS.

Novel NiMoW-clay hybrid composites are easily prepared by using organic cations modified clay montmorillonite (organo-MMT) as support. And the active component metal ions could be easily uniformly dispersed into interlayer space of organo-MMT. The as-fabricated hybrid catalyst exhibits substantially improved activity for hydrodesulfurization (HDS) reaction of dibenzothiophene (DBT) with the sulfur removal of 99.8%. In addition, this catalyst also shows outstanding HDS activity with the sulfur removal of 99.8% and wonderful stability during 168 h for industrial kerosene (2400 ppm S).

Ultra-deep desulfurization is a major requirement for upgrading the quality of fuel and power sources for fuel-cells. A series of mesoporous TiO

Chemical doping has been recognized as a promising route to achieve novel physicochemical functions of porous carbons as metal-free catalysts in renewable energy-related technologies, such as electrochemical oxygen reduction reaction (ORR). However, it remains challenging to exploit an effective method for the synthesis of metal-free carbonaceous electrocatalysts. Herein, we report the direct synthesis of phosphorus-doped mesoporous carbonaceous electrocatalysts for the first time through soft-templating method, in which organophosphonic acid serves as the phosphorus source. The resulting mesoporous carbon material possesses high doping level, large surface area, and an interconnected mesopore system, ensuring the sufficient exposure and availability of catalytic sites to realize considerable catalytic activity for ORR in alkaline media. More importantly, much better tolerance for methanol oxidation, higher durability, and comparable Tafel slopes as compared with the commercial Pt/carbon (Pt/C) catalyst are valuable for developing alternative fuel cells and metal–air batteries.

Heteroatom-doped porous carbons with controllable dopant species were rationally synthesized through a universal polymerization–carbonization strategy, exhibiting considerable activity, superior resistance to methanol, and strong durability towards oxygen reduction in comparison with the Pt/C benchmark, due to the doping effect and unique structural properties.

A facile method is to prepare novel CeMo

Bubbles created with ultrasound from artificial microscopic crevices can improve energy efficiency values for the creation of radicals; nevertheless it has been conducted so far only under special laboratory conditions. Limited reproducibility of results and poor energy efficiency are constraints for the sonochemistry and ultrasonics community to scale-up applied chemical processes. For the first time, using conventional ultrasonic bath technology, the numbering-up and scale-up of a microfluidic sonochemical reactor has been achieved. Sonochemical effects such as radical production and sonochemiluminescence were intensified by the modification of the inner walls of a novel Cavitation Intensification Bag. While 25 times bigger than the previous microreactor, a reduction of 22 % in standard deviation and an increase of 45.1 % in efficiency compared to bags without pits were obtained. Mechanical effects accompanying bubble collapse lead to two distinct types of erosion marks observed in the bags.

At neutral pH value and room temperature, nanoporous silica has been prepared through self-organization of synthetic block copolypeptide Poly(ethyl glycol)-b-poly(L-phenylalanine) (MPEG44–b-Phe7) and silicane in the organic gel system. In this system, π－π interaction between anilino-methyl triethoxy silicane and block copolypeptide MPEG44–b-Phe7 effectively controlled the growth of the silica precursors. SEM images show that the size of silica is relatively uniform with the length ranging from 20~50 μm and the diameter ranging from 2~5 μm. FT-IR spectra reveals that there exists nanoporous structure in the calcined sample. N2 adsorption-desorption isotherms are consistent with the results of FT-IR spectra and show a type-IV isotherm with H1-type hysteresis loop, which means the presence of uniform nanoporous structure. This sample has a BET surface area of 171 m2.g-1 and a pore volume of 0.55 cm3.g-1. The average pore size calculated by BJH method is 10 nm. Our results suggest a new biomimetic avenue for synthesis of nanoporous inorganic materials templated by the self-organization of copolypeptide .

A USB bus based data interface technology for full auto Patch-Clamp system is discussed in the article. The main controller is CY2131QC (Cypress) and the logic controller is EPM3256A (Altera). Optocouplers are used to get rid of the noise from the interface. It makes the installation of the Patch-Clamp system easier by using the USB bus, and is suitable for the new generation of the Patch-Clamp system with a high speed of 1M bytes/s.