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A NaA zeolite shows exceptionally high selectivity for radioactive 90Sr2+. Structural Rietveld refinements reveal that all Sr2+ ions are located at the center of the s6rs of lta cages.

Water pollutants existing in their oxyanion forms have high solubility and environmental mobility. To capture these anionic pollutants, cost-effective inorganic materials with cationic frameworks and outstanding removal performance are ideal adsorbents. Herein, we report that two-dimensional (2D) cationic aluminoborate BAC(10) sets a new paradigm for highly selective and efficient capture of Cr(VI) and other oxyanions from aqueous solution. The structure of Cr(VI)-exchanged BAC(10) sample (Cr(VI)@BAC(10), H

A surface with a smart wettability transition has recently been proposed to enhance the boiling heat transfer in either macro- or microscale systems. This work explores the mechanisms of bubble nucleation on surfaces with wettability transitions at controlled temperatures by molecular simulations. The results of the interaction energy at the interface and potential energy distribution of water molecules show that the nanostructure promotes nucleation over the copper surface and causes lower absolute potential energy to provide fixed nucleation sites for the initial generation of the bubble nucleus and shortens the incipient nucleation time, as compared to the mixed-wettability or hydrophilic nanostructure surface. An investigation on more nanostructured surfaces shows that a surface (F) with a wettability transition temperature of 620.0 K has the shortest average incipient nucleation time at 1672 ps with a wall temperature of 634.3 K. The surface with tunable wettability has also a high interfacial thermal conductance at low superheats, but it may not promote the critical heat flux at high superheats. The heat-transfer performance of the smart surface is better than the plate, the hydrophobic nanostructure, and the mixed-wettability surfaces, while it is lower than the hydrophilic nanostructure surface. This proposes a new method and provides insight for promoting bubble nucleation on a surface with temperature-dependent wettability.

Capturing volatile radionuclide iodine produced in the nuclear industry is a crucial environmental issue. In previous studies, the principal efficient adsorbent for iodine capture was silver-containing zeolite. As silver-containing zeolites are expensive, alternate copper-loaded porous zeolites, including CuCl loaded NaY reduced by H

Solid-state lithium (Li)–air batteries are recognized as a next-generation solution for energy storage to address the safety and electrochemical stability issues that are encountered in liquid battery systems1–4. However, conventional solid electrolytes are unsuitable for use in solid-state Li–air systems owing to their instability towards lithium metal and/or air, as well as the difficulty in constructing low-resistance interfaces5. Here we present an integrated solid-state Li–air battery that contains an ultrathin, high-ion-conductive lithium-ion-exchanged zeolite X (LiX) membrane as the sole solid electrolyte. This electrolyte is integrated with cast lithium as the anode and carbon nanotubes as the cathode using an in situ assembly strategy. Owing to the intrinsic chemical stability of the zeolite, degeneration of the electrolyte from the effects of lithium or air is effectively suppressed. The battery has a capacity of 12,020 milliamp hours per gram of carbon nanotubes, and has a cycle life of 149 cycles at a current density of 500 milliamps per gram and at a capacity of 1,000 milliamp hours per gram. This cycle life is greater than those of batteries based on lithium aluminium germanium phosphate (12 cycles) and organic electrolytes (102 cycles) under the same conditions. The electrochemical performance, flexibility and stability of zeolite-based Li–air batteries confer practical applicability that could extend to other energy-storage systems, such as Li–ion, Na–air and Na–ion batteries. Flexible, stable and energy-dense solid-state Li–air batteries are realised using ultrathin, chemically inert ion-conductive zeolite membranes as a solid electrolyte.

A liquid chromatography−mass spectrometry method was developed for the simultaneous quantitation of (2R,3R)-Dihydromyricetin and Myricetin in rat plasma samples to facilitate analysis of samples collected after administration of SenDeng-4 medicine. The plasma was subjected to protein precipitation with HCl (containing 10% ascorbic acid) and analyzed using electrospray ionization mass spectrometry in selected ion monitoring mode with Paeoniflorin as an internal standard. Good linearity for the two compounds was observed. The intra- and inter-day precision of analysis was

Functional nanoporous materials are widely explored for CO2 separation, in particular, small-pore aluminosilicate zeolites having a “trapdoor” effect. Such an effect allows the specific adsorbate to push away the sited cations inside the window followed by exclusive admission to the zeolite pores, which is more advantageous for highly selective CO2 separation. Herein, we demonstrated that the protonated organic structure-directing agent in the small-pore silicoaluminophosphate (SAPO) RHO zeolite can be directly exchanged with Na+, K+, or Cs+ and that the Na+ form of SAPO-RHO exhibited unprecedented separation for CO2/CH4, superior to all of the nanoporous materials reported to date. Rietveld refinement revealed that Na+ is sited in the center of the single eight-membered ring (s8r), while K+ and Cs+ are sited in the center of the double 8-rings (d8rs). Theoretical calculations showed that the interaction between Na+ and the s8r in SAPO-RHO was stronger than that in aluminosilicate RHO, giving an enhanced “trapdoor” effect and record high selectivity for CO2 with the separation factor of 2196 for CO2/CH4 (0.02/0.98 bar). The separation factor of Na-SAPO-RHO for CO2/N2 was 196, which was the top level among zeolitic materials. This work opens a new avenue for gas separation by using diverse silicoaluminophosphate zeolites in terms of the cation-tailored “trapdoor” effect., The sodium form of silicoaluminophosphate RHO zeolite exhibits a pronounced cation-tailored “trapdoor” effect, showing an unprecedented selectivity adsorption separation performance for CO2/CH4 and CO2/N2.

How surface wettability affects boiling heat transfer is still a challenging problem at nanoscale. In this work, a three-dimensional analysis of surface potential energy is used to address its relationship to surface wettability and nanoscale pool boiling characteristics of liquid molecules. It is found that the major reason for the enhanced heat transfer by increasing the surface wettability is essentially the improvement of surface potential energy, of which the influence is summarized using logic order. Moreover, the nanoscale boiling of water on copper surfaces with various wettability is investigated, which reveals that the increase in surface wettability can improve the heat transfer coefficient and critical heat flux under high superheat conditions in both nano- and macroscale systems. Besides, the effects of surface potential energy on contact angle, Kapitza resistance, heat transfer coefficient, and critical heat flux are analyzed systematically to demonstrate their relationships. A nondimensional analysis is finally implemented to correlate the normalized surface potential energy (P), the Nusselt number (Nu), and the normalized critical heat flux (J): Nu = 0.081P0.34, J = 0.827P0.50 (P 2.387). This work provides insights into the enhancement mechanisms for the phase-change heat transfer of liquid molecules over surfaces with different wettability.

Nanostructure can apparently affect explosive boiling through surface roughness that functions as a cavity for activating the bubble nucleus. In this work, the effect of surface roughness on the explosive boiling of water film over the copper surfaces with nanochannels having different heights and spacing is investigated. It is found that the increase in the roughness ratio by raising the channel height can substantially promote the onset time of boiling, increase the temperature and heat flux of water, and reduce the interfacial thermal resistance. The increase in roughness ratio by reducing the channel spacing has a promotion effect first and then a weakening effect on the boiling heat transfer. A critical channel spacing is proposed to address this effect on boiling heat transfer on surfaces with increasing roughness ratio by reducing the channel spacing. Moreover, a two-dimensional surface potential energy is used to address the relationship among the roughness ratio, interaction potential energy, and explosive boiling characteristics of the liquid molecules on the structured surfaces. The absolute value of surface potential energy increases with increasing roughness ratio with an increase average rate of 7.1 eV. It is concluded that, when the channel spacing exceeds the critical value, the major reason for the enhanced heat transfer by increasing the roughness ratio is essentially the improvement of the surface potential energy by increasing the heat transfer area. Further investigations on nanochannels with different heights and spacing indicate that the critical channel spacing of 1.444 nm is also suitable for more nanochannel surfaces. The findings of this study can help for a better understanding of the mechanisms of explosive boiling of various fluids on nanostructured surfaces by the surface potential energy.

The boiling of liquid water on the superalloy surface is important in applications such as steam and gas turbines, for which it is necessary to explore the mechanisms of the Leidenfrost phenomenon. The molecular dynamics simulation method provides an effective way to study this phenomenon at the nanoscale. Previous studies, however, have not revealed the Leidenfrost effect of liquid molecules on a superalloy surface. This work investigated the effects of surface temperature and impact velocity on the nanoscale Leidenfrost phenomenon of water droplet over the Fe-Cr superalloy plate. When the surface temperature is higher than 798 K, the Leidenfrost phenomenon occurs on the superalloy surface with apparent temperature, stress, and pressure differences. The results indicate that the Leidenfrost phenomenon is related to the high surface temperature, rather than its impacting velocity. Furthermore, it is found that the Leidenfrost phenomenon is the combined results from the temperature and pressure differences exist in the vapor film, as enough kinetic energy can be generated by the thermal motion to cause the bounce phenomenon of droplet. The revealed mechanisms are critical for the design of a gas turbine, in which vapor film could be dominant in determining the film cooling effectiveness of gas/vapor on the blade surface.

This work investigated the effect of liquid film thickness and surface roughness ratio on the rapid boiling of water over the copper plates in terms of hydraulic diameter defined based on the overall cross-sectional area available for the flow of water film. It is found that the reduction of the hydraulic diameter by increasing the surface roughness ratio can substantially promote the performance of rapid boiling, because of the increase in heat transfer area, together with a decrease in the Kapitza resistance. As a combined effect of the film thickness and the Wenzel roughness ratio, the hydraulic diameter can determine the onset time of boiling and the equilibrium temperature, while it can also determine the heat transfer rate and the Kapitza resistance if the film thickness or the surface roughness is fixed. The effects of the hydraulic diameter on the performances of nanoscale boiling can be applied for heat transfer enhancement and process intensification over any structure in phase-change devices and chemical equipments.

Surface temperature and wettability can synergistically affect the performance of explosive boiling which is important for many industrial processes. This work investigated the explosive boiling of water film over copper surfaces with different wettability under various surface temperature conditions. The results show that the water molecules on the hydrophilic surfaces have higher temperature gradient and initial heat flux, shorter onset time of boiling, and lower Kapitza resistance than those on the hydrophobic surface. Meanwhile, the temperature gradient, the heat flux in the water films, and the onset time of explosive boiling are promoted by elevating the surface temperature. These indicate that the hydrophilic surface under high surface temperature conditions is most favorable for enhancing the explosive boiling heat transfer. Analysis of the onset of boiling reveals that the effect of wettability on the explosive boiling is more prominent under low surface temperatures but is limited under high surface temperatures. This work provides insights into the mechanisms of liquid molecules behaviors on plate surfaces with different wettability and surface temperatures for phase-change heat transfer enhancement and process intensification.

This paper presents a 0.13μm 64Mb HfOx ReRAM for embedded storage in IoT device. The configurable ramped voltage write and low read-disturb sensing techniques are proposed to address the reliability challenges in ReRAM. Experimental results show that, the ReRAM chip achieves more than 107 cycles' endurance and 10 years' retention at 75°C. In addition, its full function and superior random write performance are demonstrated on a developed evaluation board.

The main subject of this thesis is to study a uneasily two-wheeled self-balancing vehicle system. Two tires are placed on two sides of the body parallel in this system . Controlling the rotation of two DC motors can achieve the goal of walking upright. The circuit part is mainly made up by attitude sensors parts (including Gyroscope and Accelerometer), control circuit and the driver board. Attitude sensors measure the tilt angle and the rate of change of inclination of vehicle, and then the controller calculate the responding data and finally drive two DC motors forward or backward to produce forward or backward acceleration to make the car balancing.

To exploit an effective adsorbent to separate hydrogen and methane, microporous titanium silicate molecular sieve NaETS-4 was synthesized and modified by strontium. The adsorption characteristics and diffusion behaviors of the prepared titanosilicate molecular sieve were studied by concentration pulse chromatography. And the effects of ion-exchange and dehydration temperature on adsorbent structure and gas diffusion were also discussed. The results showed that the thermal stability and Henry's Law constants were enhanced and micropore diffusivity decreased after exchanging Na + with Sr 2+ . With the increase of dehydration temperature, Henry's Law constant and micropore diffusivity of CH 4 decreased in both NaETS-4 and SrETS-4. While for H 2 in SrETS-4, the increase of Henry's Law constant and the decrease of diffusion rate can be attributed to the shrinks of pore diameter resulting from the relocation of Sr 2+ . Correspondingly, the kinetic selectivity of H 2 /CH 4 reached 8.91 indicating its potentiality in separating H 2 and CH 4 .

Reconfigurable solid state drive platform is necessary for the evaluation of emerging non-volatile memories. In this paper, we design a solid state drive prototyping system based on Xilinx Zynq chip, and further implement a ReRAM-based solid state drive system. ATTO Disk Benchmark is used to test the potential performance benefit of ReRAM-based storage. The superior random write performance demonstrates that ReRAM is promising for big data applications.

We study the structure of a metric n-Lie algebra \(\mathcal{G}\) over the complex field ℂ. Let \(\mathcal{G} = \mathcal{S} \oplus \mathcal{R}\) be the Levi decomposition, where \(\mathcal{R}\) is the radical of \(\mathcal{G}\) and \(\mathcal{S}\) is a strong semisimple subalgebra of \(\mathcal{G}\). Denote by \(m\left( \mathcal{G} \right)\) the number of all minimal ideals of an indecomposable metric n-Lie algebra and \(\mathcal{R}^ \bot\) the orthogonal complement of R. We obtain the following results. As \(\mathcal{S}\)-modules, \(\mathcal{R}^ \bot\) is isomorphic to the dual module of \({\mathcal{G} \mathord{\left/ {\vphantom {\mathcal{G} \mathcal{R}}} \right. \kern-\nulldelimiterspace} \mathcal{R}}\). The dimension of the vector space spanned by all nondegenerate invariant symmetric bilinear forms on \(\mathcal{G}\) is equal to that of the vector space of certain linear transformations on \(\mathcal{G}\); this dimension is greater than or equal to \(m\left( \mathcal{G} \right) + 1\). The centralizer of \(\mathcal{R}\) in \(\mathcal{G}\) is equal to the sum of all minimal ideals; it is the direct sum of \(\mathcal{R}^ \bot\) and the center of \(\mathcal{G}\). Finally, \(\mathcal{G}\) has no strong semisimple ideals if and only if \(\mathcal{R}^ \bot \subseteq \mathcal{R}\).

The effects of single or combined stress of aluminum (Al) and chromium (Cr) on plant growth, root dehydrogenase, oxidative stress and antioxidative enzymes were studied using two barley genotypes differing in Al tolerance in a hydroponic experiment. Al or Cr stress decreased plant growth, lowered root dehydrogenase activity and caused oxidative damage, as characterized by increased MDA and H2O2 contents. Under Al or Cr stress, the activities of antioxidative enzymes, including superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) and catalase (CAT), were dramatically increased in plant tissues. Gebeina, an Al-tolerant genotype, had less oxidative damage than Shang 70-119, an Al-sensitive genotype. The extent of oxidative damage induced by Cr varied with the pH of the culture solution, with lower pH values (4.0) being more severe than higher pH values (6.5). The combination of Cr and Al caused a further decrease in plant growth, a decrease in root dehydrogenase activity and an increase in MDA and H2O2 contents as well as the activities of antioxidative enzymes. There was also a marked difference between the two barley genotypes in the extent of increased antioxidative enzyme activity under the Cr and Al stresses.

The hydrolysis–polycondensation (HP) products of tetraethoxysilane (TEOS) in various pH media were introduced as silica sources in the synthesis of zeolite A nanocrystals. The synthesized sample had the minimum Si/Al ratio and crystal size when the HP process happened in the natural medium. With the increase of acidity or basicity of the HP process, both the Si/Al ratio and the crystal size of samples also increased. However, the sample had a trace amount of FAU phase and the lowest crystallinity when the basicity of the HP process was strong. The diverse properties of samples were essentially due to the polymeric state of silicate precursors that resulted from different HP processes of TEOS in various pH media.

In this paper, we mainly study the structural notions of Frattini subalgebra and Jacobson radical of n-Lie algebras. The properties on Frattini subalgebra and the relationship between the Frattini subalgebra and Jacobson radical are studied. Moreover, we also study them when an n-Lie algebra is strong semi-simple, k-solvable and nilpotent.

The mathematical representing or fitting articular surface of the human knee joint based on the experimental measurements is very important for biomechanical studies and clinic rehabilitation engineering. But, so far this work still maintains a challenge due to the human knee joint exhibits a complicated surface geometry. In this paper, based on the literatures [1-17], a review and comparison on the techniques of the articular surface representing or fitting at the human knee joint are presented.

With the progress of scientific technology and development of production, measurement technology of dynamic torque has been widely applied to lots of fields of national economy. In different fields, the measurement method of dynamic torque is not the same. This paper describes a method for measuring dynamic torque by swiveling angle of the magnetic yoke, designs and implements an acquisition system of dynamic torque. The system can achieve many functions, for example, it can collect 16-ways parallel digital signal, analyze and display oscillogram and so on, through analyze and process real-time oscillogram, we can measure the instantaneous value of swing angle, by which we can accurately obtain the instantaneous dynamic torque.