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Artificial intelligence (AI) has been rapidly developing over the past few years, radically changing how we interact, plan, and leverage technology in our everyday lives. The latest National Defense Strategy [...]

The efficient cleaning conversion of coal is more and more attracted due to resource exhaustion and environmental pollution. To improve the yield and quality of products of coal pyrolysis, the catalytic hydrogenated microwave pyrolysis was introduced, and the effects of metal sulfide on hydrogenated microwave pyrolysis were focused on discuss via the detection methods of proximate and ultimate analyses, SEM-EDS, FT-IR and GC-MS in this work. The results shown that because of the “hot-spot” effect and the characteristics of electromagnetic loss of metal sulfide, the temperature-rising rates with catalysts were obviously higher, but the final pyrolysis temperatures with or without catalyst were almost close. Higher temperature-rising rate with catalysts made the yield of liquid product more, which the yields of liquid product with MoS2 and FeS2 catalyst were 28.4 wt.% and 27.1 wt.%. The carbon distributions indicated that carbon in solid and gaseous products transferred into liquid product, when the catalysts added into pyrolysis reactions. The quality of tar with catalyst was improved, and the component content of light oil, intermedium oil and heavy oil were 67.55 wt.%, 27.98 wt.% and 4.47 wt.% for MoS2 catalyst, in which the content of light oil increased by 10.30 times than that without catalyst. The thermal effect and catalysis of metal metal sulfide made complex aromatic compounds more thorough cracking, improved the amount and active of free hydrogen. Actived free hydrogen further enhanced cracking of heavy oil, resulting in the content of hydrogen in gaseous with catalysts decrease, and the content of light oil increased.

A novel visible-light-promoted C–P bond formation reaction in the absence of both transition metal and photoredox catalysts is disclosed. By employing easily available and inexpensive heteroaryl chlorides/bromides as substrates, a variety of heteroaryl phosphine oxides were obtained in moderate to good yields. This strategy provides a simple and efficient route to heteroaryl phosphine oxides.

In this study, sensitivity analysis and optimization were performed to evaluate the effects of structural parameters on the charging performance of a phase change material (PCM) based multi-tube heat exchanger. The structural parameters included the number of inner tubes (factor A), the ratio of eccentric distance to shell radius (factor B), the angle ratio (factor C) and the thickness of tube wall (factor D), and the objective function was the mean charging rate. The main objective of the present study was to identify the optimum structural parameters for the maximum charging rate enhancement. For a multi-tube heat exchanger with uniformly distributed inner tubes, the influence degree of structural parameters on charging performance was studied using Taguchi method. By variance analysis of the trial results, it found that factor A has a very significant effect on the mean charging rate, factor B has a significant effect, while factor C and factor D have no significant effect. Furthermore, taking the multi-tube heat exchanger with five tubes as a research object, the non-uniform distribution of tube positions was optimized by genetic algorithm. As compared with the case of uniform distribution of inner tubes, the optimal one increased the mean charging rate by 5.21 %.

Aluminum nitride (AlN) power was successfully synthesized by direct nitridization method heating for 4h at 950°C with magnesium (Mg) and ammonium chloride (NH4Cl) as additives. The morphology and microstructure of nitride product were done by XRD and SEM. Result reveals that the nitride producs was pure hexagonal phase. In addiation, whiskers in the power which diameter is at the nanoscale and length ranging from a few microns were also observed, and EDS test displays the component of whiskers is AlN.

The hydrodenitrogenation (HDN) of Longkou shale oil were carried out in microscale trick-bed reactor over a commercial NiW/Al2O3 catalyst with high HDN activity. The effects of temperature, pressure, liquid hourly space velocity (LHSV) and hydrogen/oil ratio on the conversions of total, basic and non-basic nitrogen compounds were investigated at various conditions (340-420oC, 0.2-2h-1, 4-9MPa and 400-1000 L/L). The results show that basic nitrogen compounds have higher HDN reactivity than non-basic nitrogen. The distributions and species of nitrogen compounds in Longkou shale oil were also investigated. About 33% of total nitrogen is present in big molecules with high boiling point. The nitrogen compounds in Longkou shale oil are mainly composed by seven kinds of components ( nitriles, anilines, pyridines, quinolines, acridines, carbazoles and indoles).

New lumping kinetic models, considering the effects of the nitrogen content in product and the correction coefficient of LHSV, were proposed to describe the hydrodesulfurization of crude Longkou shale oil. The kinetic parameters were obtained using nonlinear regression of the experimental data which were conducted in a bench-scale trick-bed reactor with NiW/Al2O3 catalyst at various conditions. The results show that the 4-lump model is the optimal model. The values of apparent activation energies of lumps 1, 2, 3 and 4 are 51.14, 62.64, 130 and 166.42kJ/mol, respectively. The validation and application of the 4-lump model were also investigated.

The thermogravimetry - differential thermal analysis (TG-DTA) and theoretical analysis method of Coats-Redfern were employed to study the pyrolysis process and kinetics characteristics of mixture containing lime-mediated sewage sludge and gas ash, then sintering cup test the different proportion of mixture ball. It was found that the pyrolysis process of mixture from indoor temperature 1200°Ccould divided into 4 the weight loss stages, which brings a large number of heat and CaO, Fe2O3. Base on the results of Coats-Redfem integration method, the pyrolysis process of mixture under air atmosphere was belongs to two-class reaction. Sintering cup test show that lime-mediated sewage sludge and gas ash replacing part of the sintering ingredients is feasible.

This paper describes the setup of a complex voltage ratio measurement system for the audio frequency range. A wideband two-channel digitizer and a differential analogue channel switching front-end are used as the heart of the system. The complex error, frequency response characteristics and short term stability of the system are tested in this paper. The errors range from 1×10-7 at 50 Hz to 10×10-6 at 200 kHz in ratio 1:1 test with 6 V input voltages. And errors are below ±8×10-7 and ±0.06 μrad in ratio 1:1 test with a 4V power line (50 Hz) input voltage over 64 hours. The test results and comparisons between with and without channel exchange mode confirm the remarkable improvement regarding the suppression of the static mismatch errors of the digitizer and show the usefulness of the system at 50 Hz too.

We study the coherent transport of a single photon in a one-dimensional coupled-resonator array, nonlocally coupled to a two-level system. Since its inherent structure is a Mach-Zehnder interferometer, we explain the destructive interference phenomenon of the transmission spectra according to the effect of which-way detection. The quantum realization of the present model is a nanoelectromechanical resonator array with two nearest resonators coupled to a single spin via their attached magnetic tips. Its classical simulation is a waveguide of a coupled-defected cavity array with double couplings to a side-defected cavity. [ABSTRACT FROM AUTHOR]

We study how an oscillating mirror affects the electromagnetically induced transparency (EIT) of an atomic ensemble confined in a gas cell, which isplaced inside a microcavity with an oscillating mirror in one end. The cavity field acts as a probe of the EIT system and also produces a light pressure on the mirror. The back-action from the mirror to the cavity field results in several (from one to five) steady-states for this atom-assisted optomechanical cavity, producing a complex structure in its EIT. The multiequilibnum positions of the oscillating mirror have been calculated, and then the susceptibility is studied with respect to the different equilibrium positions. We find that the EIT of the atomic ensemble can be significantly changed by the oscillating mirror, and also the various steady states of the mirror have different effects on the EIT. [ABSTRACT FROM AUTHOR]

We study a hybrid nanomechanical system coupled to a spin ensemble as a quantum simulator to favor a quantum interference effect, electromagnetically induced transparency (EIT). This system consists of two nanomechanical resonators (NAMRs), each of which is coupled to a nuclear spin ensemble, and can be regarded as a crucial element in the quantum network of NAMR arrays coupled to spin ensembles. Here, the nuclear spin ensembles behave as a long-lived transducer to store and transfer the NAMRs' quantum information. This system shows the analog of the EIT effect under the driving of a probe microwave field. The double EIT phenomenon emerges in the large-N (the number of nuclei) limit within the low excitation approximation, because the interactions between the spin ensemble and the two NAMRs are reduced to the coupling of three harmonic oscillators. Furthermore, the group velocity is reduced in the two absorption windows. [ABSTRACT FROM AUTHOR]

A resonant two-level atom doped in a one-dimensional waveguide behaves as a mirror, but this single-atom "mirror" can only reflect single photons perfectly at a specific frequency. For a one-dimensional coupled-resonator waveguide, we propose to extend the perfect-reflection region from a specific frequency point to a wide band by placing many atoms individually in the resonators in a finite coordinate region of the waveguide. Such a doped resonator array promises to control the propagation of a practical photon wave packet with a certain momentum distribution instead of a single photon, which is ideally represented by a plane wave with a specific momentum. The studies based on the discrete-coordinate scattering theory indicate that such a hybrid structure with finite atoms indeed provides a near-perfect reflection for a single photon in a wide band. We also calculated the photon group velocity distribution, which shows that the perfect-reflection wide band exactly corresponds to the stopping light region. [ABSTRACT FROM AUTHOR]

To apply copper alginate fibers in medical as a new alginate fiber, copper alginate fibers were researched and evaluated against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus), using antibacterial zone and flash shaking method to analyze anti-bacterial mechanism by the scanning electron microscopy (SEM). The results showed that copper alginate fibers had antibacterial effects, the antibacterial rate against E.coli and S.aureus were 97.4% and 66.2%, respectively; SEM images indicated that bacteria obviously changed after contacting with fibers, the main reason was that copper ion had a damaging effect on pericellular and cell wall. Furthermore, bacterial osmotic pressure was changed and protein synthesis were impeded, and then the normal metabolism of bacteria was destroyed, and finally, bacteria died.

The cytotoxicity and anti-influenza virus (IFV) activity of calcium or zinc alginate fibers were investigated to explore the feasibility of them to be used as biomaterials. African Green Monkey kidney cell (Vero) and human cervical cancer cell (Hela) cultured with alginate fibres were used to screen cytotoxic effects. After 48 h, MTT (3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H tetrazolium bromide) assays were performed. Then cytotoxicity was evaluated with six grades according to cell relative growth rate (RGR). In anti-IFV activity assay, IFV were added to all fibers and the Vero cell survival were detected by MTT assays with calculating the percentage of protection. The cytotoxity of calcium alginate fibers on Vero were grade 0 or 1 in contrast to zinc alginate fibers which was grade 0. The cytotoxity of calcium or zinc alginate fibers on Hela were grade 0. Furthermore, partial calcium or zinc alginate fibers could promote Vero or Hela cell growth. In antiviral assay the highest percentage of protection of calcium alginate fibers was 34.42%, while that of zinc alginate fibers was 59.42%. The results showed that calcium or zinc alginate fibers had a good cellular biocompatibility and the large weight zinc alginate fibers had a better anti-IFV activity than calcium alginate fibers, which is potential for tissue engineering.

The sealing performance of a brush seal is studied in this article. At present, the mostly used model to analyze the performance of a brush seal is porous medium model in which the effect of bristle deformation is not considered. Here, a combined numerical method is proposed. First, the deformation of bristle is calculated in a fluid–solid coupling model with a simplified bristle model, and then the results of the bristle deformation is imported to a porous media model as the boundary conditions. More accurate media flow and leakage variation law of the brush seal are obtained with this calculation model.

Bulk metal, in general, never absorb such abundant D/H atoms as to exceed the host metal atom density, and so, these D-atoms cannot be approachable each other at all even atomic distance of their molecule within the bulk metal. As a result, they never cause nuclear fusion within the bulk metal (ever bulk Pd). On the contrary, nano-metal, such as nano-Pd (isolated ≪ ϕ150 Å, embedded ≤ ϕ50 Å in size), instantly absorbed abundant D/H atoms up to levels as high as 300% of Pd metal density. These absorbed atoms were solidified densely inside each unit cell of the host lattice as solid-state “Pycnodeuterium”/“Pycnohydrogen”. Moreover, we developed not only nano-Pd metal but also new materials which show similar behavior with nano-metal under bulk-state. In a word, peculiar bulk oxidized compound absorbed abundant D/H atoms and solid-state “Pycnodeuterium”/“Pycnohydrogen” were produced within throughout their bulk materials. Pycnodeuterium with stimulation energy easily caused intense solid-state nuclear fusion, whereas in case of Pycnohydrogen no reaction occurred. As a result, it was clarified that Pycnodeuterium is by far the best nuclear fuel compared to all other nuclear fuels just as “gaseous deuterium” against the “thermonuclear fusion”.

The deuterium concentration in the bulk Pd metal used as a cathode in the electrolysis of D2O is found to be much less than that in fine Pd powders of the nano-scale in a double-structure (DS) cathode. In marked contrast to the case with the DS cathode, neither excess heat nor 4He production are observed with the bulk Pd cathode.

Both D2O-cell and H2O-cell are constructed with the same Double Structure Cathode (DS-cathode), and connected in series as a "Double-cell" to examine the energy generation under the same electrolytic current. D2O-cell generates tremendously excess energy during a long period such as over several thousand hours, but any energy is never generated in H2O-cell when the chemical energy is subtracted in both cells. Furthermore, "Mixed-cell" blended with D2O and H2O electrolytes (D2O/H2O=2 in weight) also generates an excess energy, but with the considerably different characteristics from D2O-cell.

Observations were made of the anomalous production of 4He atoms as well as the anomalous heat release when Pd fine particles are highly deuterated inside an enclosed Pd metal vessel used as a cathode in electrolysis of D2O. A mass analysis of the remnant Pd powders after the 2000-hr heat production revealed substantial production of 4He atoms.