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ABSTRACTWith developments in information technology, multimedia equipment and electronic teaching aids have been introduced into primary and secondary school classrooms. Thus, traditional “blackboards” have gradually given way to screens, ultimately complicating the visual environment and the visual act of looking at the blackboard. Generally, looking at the blackboard can affect the visual comfort of students when reading from different viewing distances. In this study, 40 primary school students were invited for a visual perception human-factor experiment in a secondary school classroom in Anshan, Liaoning Province, China. The Ergo LAB human-factor platform was used to test the students’ electrodermal indicators at different distances. Moreover, simultaneous subjective scoring was performed to compare and analyse the students’ state of arousal levels and visual perceptual comfort under different visual distance conditions. The acceptable visual distance for students to be able to read from an electronic screen ranged from 2.2 m to 8.5 m; the highest state of arousal and visual comfort were achieved at a visual distance of 4–4.9 m, and the most optimal visual distance was 5.8 m.

Glass direct current product USES the uA level, LED chip light‐emitting efficiency under different temperature differences. Because of the glass substrate, high thermal conductivity, glass and metal bracket assembled light board, due to the contact position and not contact position Z to thermal resistance difference is bigger, results in a larger temperature difference in the surface, lead to white picture, stimulation and phenomenon of tic‐tac‐toe grid. Analyze the lamp plate heat source, according to the thermal distribution of different location, by adopting insulation tape, multilayer graphite flake scheme improve lamp plate to the heat conduction ability, X/Y for COF package IC and light insulating board contact with the aluminum frame position, improve the mold inside lamp panel heat distribution. Test: by improving measures after the light in the same drive power module can be glass straight under in‐plane horizontal arrows temperature reduced from 2.5 ℃ to 1.4 ℃, the improved white showing effect.

Since the 13th Five-Year Plan, Sinopec has been thoroughly carrying out the new energy security strategy of “four revolutions and one cooperation” and the spirit of the important instruction of “powerful promotion of petroleum exploration and development”. Focusing on strategic breakthrough and large-scale reserve increase, the petroleum exploration enhances the theoretical and technological innovation and highlights high-quality exploration battles, so that a series of important petroleum exploration achievements have been gained. In order to accelerate and promote the development of Sinopec's natural gas business, this paper forecasts Sinopec's exploration direction and development potential of natural gas in the future after comprehensively sorting out the achievements and theoretical and technological progresses of natural gas exploration since the 13th Five-Year Plan. And the following research results are obtained. First, since the 13th Five-Year plan, Sinopec has been persisting in the strategic deployment of “balancing marine and continental facies and focusing conventional and unconventional resources”. According to the idea of “extending marine conventional gas, strengthening marine shale gas and optimizing continental tight gas”, Sinopec innovatively develops the hydrocarbon accumulation theory of marine shale gas in southern China, marine carbonate rock in central–western China and tight clastic rock in central–western China. Second, by virtue of researches, a 3D seismic exploration technology with reservoir identification and description as the basis and sweet spot prediction as the core is developed, and several support equipment and tools are integrated, such as deep and ultra-deep drilling and completion, acid fracturing testing, long horizontal well fracturing and high power electric fracturing, and drillable composite bridge plug. Third, a series of natural gas exploration achievements are obtained in three major fields of marine shale, marine carbonate rock and continental tight clastic rock, and new proven natural gas reserves of 1.0068 × 1012 m3is achieved, which provides Sinopec with high-quality resource guarantee for the fast increase of natural gas production. Fourth, looking forward, there are abundant natural gas resource bases in Sinopec's licenses, and the main development directions of its natural gas exploration are marine carbonate rock in central–western China, tight clastic rock and shale in central–western China, marine deep clastic rock, and deep clastic rock and igneous rock in the mature areas of eastern China. In conclusion, Sinopec's new proven natural gas reserves during the 14th Five-Year Plan is predicted to be 1.16 × 1012–1.36 × 1012 m3, which can provide a solid resources base for the great development of natural gas in China.

With the recognition that carbonate reservoir rocks commonly contain a significant microporosity component [pore sizes ~1 pm), there has been an ongoing effort to understand how this affects hydrocarbon recovery. This work reports x-ray microtomography (XMT) and nuclear magnetic resonance [NMR] data on two characteristic rock types. One is micropore dominated, and the other exhibits mixed-pore sizes. Several new techniques are introduced to accommodate investigation of full-sized core-plug samples having preserved wettability and to perform such studies with native fluids. First, the uses of high-field NMR techniques are demonstrated to determine porosity, overall oil and water content, and how these fluids are distributed between micro- and macropores. It is found that microporosity values agree with those obtained by optical (total pore system) analysis. Second, the use of xenon gas to tag the native oil phase for XMT imaging is demonstrated, showing how this helps determine contributions from pores that are smaller than the instrument resolution. Finally, a new method that uses NMR measurements of oil and water saturations to constrain the image analysis is demonstrated. The analysis shows the extent to which oil recovery occurs from the different pore systems. In both rock types, oil in the macroporosity is preferentially swept. Nevertheless, in agreement with a recent theory, oil recovery from the microporosity is significant. For the 70% microporosity sample, approximately one-third of the total oil recovery comes from the micropores, a factor that agrees well with theory. [ABSTRACT FROM AUTHOR]

Four new dolabellane-type diterpene alkaloids, glandulamines A-D (1-4), together with twelve known compounds (5-16), were isolated from the seeds of Nigella glandulifera using repeated column chromatography and semipreparative HPLC. The structures of 1-16 were elucidated based on NMR data analysis, HRMS experiments and other spectroscopic interpretations. The absolute configuration of 5 was determined by single-crystal X-ray diffraction data for the first time. Compounds 10 and 12 showed human dihydroorotate dehydrogenase inhibitory activity with IC50 values of 61.1 ± 5.3 and 45.9 ± 3.0 µM, respectively. Molecular docking of the active compound 12 and positive control teriflunomide on the inhibitor-binding site of human dihydroorotate dehydrogenase was subsequently performed to visualize the interaction pattern. In addition, compounds 8 and 10 exhibited inhibitory effects against lipopolysaccharide-induced nitric oxide production with inhibition rates of 61 and 41%, respectively, at the concentration of 10 µM. Compounds 9 and 12 showed cytotoxic activities with cell viability varying from 29 ~ 57% at 100 µM against T98G, U87, U251, and GL261 glioma cancer cell lines. These data provide new insights on the pharmacologically active compounds of this plant widely used in folk medicine. [ABSTRACT FROM AUTHOR]

Because the performance of gussasphalt at high temperatures is not good enough, this article developed a composite stiffening gussasphalt that combined composite strength theory with the structure characteristics of gussasphalt and analyzed the performance of the stiffening characteristics of gussasphalt. The results showed that after using reinforcement technology, the rutting resistance in 60°C increased about 150 % and the crack resistance in 50°C, 20°C, and −10°C increased about 180 %, 23 %, and 44 %, respectively. Stiffening gussasphalt composite beam fatigue frequency was significantly higher than conventional concrete. This development has a significant effect on the steel bridge deck carrying capacity and durability.

This paper reports, for the first time, an analysis of the effect of high-current pulsed electron beam (HCPEB) on a hypoeutectic Al–10Si alloy. The Al–10Si alloy was treated by HCPEB in order to see the potential of this fairly recent technique in modifying its wear resistance. For the beam energy density of 3 J/cm2used in the present work, the melting mode was operative and led to the formation of a “wavy” surface and the absence of mass primary Si phase and eutectic microstructure. The surface nanocrystallization of primary and eutectic Si phases led to the increase in macro-hardness of the top surface layer, and the wear resistance was drastically improved with a factor of 4.

In the present study, the effects of Humulus scandensextract on growth performance, antioxidant responses and intestinal microflora of Yellow River carp (Cyprinus carpio) were investigated. 240 carps were assigned to four treatments received diets supplemented with 0 (control), 0.5, 1 and 2g/kg Humulus scandensextract for 8 weeks. At end of the trial, the final body weight, specific growth rate (SGR) and intestinal body index of the 1.0g/kg and 2.0g/kg group were significantly higher than those of the control group (P< 0.05). No significantly differences were observed for food conversation ratio (FCR) or protein efficacy ratio (PER). The SOD (superoxide dismutase) content in gills of the treatment groups was significantly increased compared to the control group (P< 0.05), GPX (glutathione peroxidase) content in gills of 2.0g/kg group was significantly higher than that of other groups (P< 0.05). Compared with the control group, the contents of SOD, CAT (catalase) and GPX in the liver of the treatment groups were significantly higher (P< 0.05). The gene expression levels of SOD, CAT and GPX in gill and liver of 1.0g/kg and 2.0g/kg group were significantly higher than those of control group (P< 0.05), and the gene expression level of HSP70 in gill and liver was decreased compared to the control group. The trypsin activity, fold height, crypt depth and goblet cell number in 1.0g/kg and 2.0g/kg group were significantly higher than those in control group and 0.5g/kg group (P< 0.05). At the phyla level, the abundance of Actinobacteriain 0.5g/kg group, Verrucomicrobiain 1.0g/kg group and Fusobacteriain 2.0g/kg group were significantly increased compare to the control group. At the genus level, compared with the control group, the abundances of Luteolibacterin 1.0g/kg group, Gemmobacterand Cetobacteriumin 0.5g/kg and 2.0g/kg groups were significantly higher. In conclusion, the present study demonstrated that 1.0g/kg-2.0g/kg level Humulus scandensextract is beneficial to growth performance, antioxidant activity and intestinal health of Yellow River carp.

We study the proton-hydrogen collision in the energy range from 0 to 5 K where the hyperfine structure of the hydrogen atom becomes important. A proper multichannel treatment of the hyperfine structure is found to be crucial at cold temperatures compared to the elastic approximation traditionally used at higher temperatures. Both elastic and hyperfine-changing inelastic processes are investigated, using both the multichannel quantum-defect theory (MQDT) and the coupled-channel numerical method. Results from the two methods show excellent agreement with MQDT providing an efficient and basically analytic description of the proton-hydrogen interaction throughout this energy range. We also discuss the validity of the elastic approximation and its relation to other methods. [ABSTRACT FROM AUTHOR]

Signal-to-noise ratio (SNR) and channel estimations are critical for 60-GHz communications to track the optimal transmission and reception beam pairs. However, the excessive pilot overhead for the estimations severely reduces system throughput in fast-rotation scenarios. In order to address this problem, we firstly demonstrate the potential sparseness property of 60-GHz channel in beam tracking; subsequently, via exploiting this property, we propose a novel compressed SNR-and-channel estimation. The estimation is conducted in a three-stage fashion, including the unstructured estimation, nonzero-tap detection, and structured estimation with nonzero- tap location. Numerical simulations show that, in the case of substantial reduction of the pilot overhead, the proposed estimator still reveals a significant improvement in terms of estimation performance over the scheme in IEEE 802.11ad. Furthermore, it is also demonstrated that the proposed SNR and channel estimators can approach the lower bounds in sparse channels so long as SNR exceeds 8 dB.

We apply the quantum-defect theory for - 1/R4 potential to study the resonant charge exchange process. We show that by taking advantage of the partial-wave-insensitive nature of the formulation, resonant charge exchange of the type of 1S + 2S can be accurately described over a wide range of energies using only three parameters, such as the gerade and the ungerade s-wave scattering lengths, and the atomic polarizability, even at energies where many partial waves contribute to the cross sections. The parameters can be determined experimentally, without having to rely on accurate potential-energy surfaces, of which few exist for ion-atom systems. The theory further relates ultracold interactions to interactions at much higher temperatures. [ABSTRACT FROM AUTHOR]

Starting from a multichannel quantum-defect theory, we derive analytic descriptions of a magnetic Feshbach resonance in an arbitrary partial wave l and the atomic interactions around it. An analytic formula, applicable to both broad and narrow resonances of arbitrary l, is presented for ultracold atomic scattering around a Feshbach resonance. Other related issues addressed include (a) the parametrization of a magnetic Feshbach resonance of arbitrary l, (b) rigorous definitions of "broad" and "narrow" resonances of arbitrary l and their different scattering characteristics, and (c) the tuning of the effective range and the generalized effective range by a magnetic field. [ABSTRACT FROM AUTHOR]

We present a fully quantal version of the Langevin model for the total rate of exoergic ion-molecule reactions or inelastic processes. The model, which is derived from a rigorous multichannel quantum-defect formulation of bimolecular processes, agrees with the classical Langevin model at sufficiently high temperatures. It also gives an analytic description of ion-molecule reactions and inelastic processes in the ultracold regime where the quantum nature of the relative motion between the reactants becomes important. [ABSTRACT FROM AUTHOR]

Two novel ester ferrocenophanes have been prepared by esterification of 1,1′-ferrocenedi(carbonyl chloride) with glycol and 1,4-butanediol, respectively. Both of them have been characterized by IR, elemental analysis, MALDI-TOF MS and 1H NMR spectroscopic methods, and their structures have been elucidated by X-ray diffraction. The intermolecular associations based on C-H···O hydrogen bonds have also been discussed. These molecules are assembled into chains, and the chains are further assembled into a 3D structure through several hydrogen bonds.

Chinese Meishan and Jiangquhai pigs are two of the most prolific pigs in the world, but their growth rate is lower than that of Duroc, Landrace and Pietrain pigs. It is suggested that growth rate is regulated by growth hormone. The objective of the current study was to analyze the porcine growth hormone (pGH) gene polymorphisms based on the polymerase chain reaction restriction fragment-length polymorphism method (PCR-RFLP) for three western meat-type breeds (Duroc, Landrace and Pietrain) and two local Chinese pigs (Meishan and Jiangquhai). Five polymorphic restriction sites were detected with theApaI,MspI,BspI andHhaI restriction enzymes in two amplified fragments (605 bp, −119 to +486; 506 bp, +206 to +711). Breed difference was found only in the 506 bp fragment. There was no difference in allelic frequencies ofBspI andHhaI restriction sites among the five breeds (P>0.05). Landrace and Meishan pigs lacked alleleG3ofMspI site. The alleleG3 frequency of restrictionMspI site of the 506 bp fragment in Pietrain pigs was higher than that in Duroc and Jianquhai pigs (P<0.001). ForApaI site, the Meishan pigs lacked alleleG1; no difference was found in allelic frequencies among Pietrain, Duroc, Landrace and Jiangquhai pigs (P>0.05). This new and rapid PCR-RFLP typing method is an attractive tool for analysis of porcine growth hormone gene restriction sites. The differences inMspI andApaI restriction sites may explain the growth difference between the foreign meat-type breeds above mentioned and local Chinese pigs.

Distinct transport proteins regulate the movement of waste products and xenobiotics across the blood-brain barrier (BBB). Members of the drug transporter families MDR, MRP, and OATP have been identified in the BBB, and a detailed characterization of the involved proteins is now required to target drugs more efficiently to the brain.

Researchers have recognized multi-agent systems (MAS) as being a promising means to cope with distributed and complex problems. However, how to analyze and design an agent-based system in practical environments is still difficult. Based on the inherent consistency between objects and agents, MAS and human social organizations, we propose an approach using comparatively mature object-oriented (OO) methodologies and tools (mostly UML) to model MAS from the point of view of organization depiction. This paper uses a distributed logistics management system (DLMS) as an example and describes a method to model MAS based on extended UML from the following three aspects:•extracting roles for agent organizations based on the theory of use cases,•depicting the static organizational structures of MAS based on the semantics and syntax of class diagrams, and•extending collaboration diagrams, sequence diagrams and state chart diagrams to portray the interactive behaviors among agent roles and the reasoning behaviors within agent roles themselves.

We derive a general relation in two-body scattering theory that more directly relates the change of density of states (DDOS) due to interaction to the shape of the potential. The relation allows us to infer certain global properties of the DDOS from the global properties of the potential. In particular, we show that DDOS is negative at all energies and for all partial waves, for potentials that are more repulsive than + 1 / r ² everywhere. This behavior represents a different class of global properties of DDOS from that described by the Levinson's theorem. [ABSTRACT FROM AUTHOR]

We demonstrate how an acoustic phonon bath when coupled to a quantum dot with the help of a bichromatic laser field may effectively form a quantum squeezed reservoir. This approach allows one to achieve an arbitrary degree of squeezing of the effective reservoir and it incorporates the properties of the reservoir into two parameters, which can be controlled by varying the ratio of the Rabi frequencies of the bichromatic field. It is found that for unequal Rabi frequencies, the effective reservoir may appear as a quantum squeezed field of ordinary or inverted harmonic oscillators. When the Rabi frequencies are equal the effective reservoir appears as a perfectly squeezed field in which the decay of one of the polarization quadratures of the quantum dot dipole moment is inhibited. The decay of the quantum dot to a stationary state which depends on the initial coherence is predicted. This unusual result is shown to be a consequence of a quantum-nondemolition-type coupling of the quantum dot to the engineered squeezed reservoir. The effect of the initial coherence on the steady-state dressed-state population distribution and the fluorescence spectrum is discussed in detail. The complete polarization of the dressed state population and asymmetric spectra composed of only a single Rabi sideband peak are obtained under strictly resonant excitation. [ABSTRACT FROM AUTHOR]

We present a quantum theory of ion-atom interactions that is applicable at energies comparable to or smaller than the atomic hyperfine splitting and takes proper account of the effects of identical nuclei. The theory reveals the subtlety and the complexity of cold ion-atom interactions including the change of threshold behavior due to hyperfine splitting and the existence of a large number and a variety of scattering resonances between hyperfine thresholds. We show how this complexity is described, efficiently and at a quantitative level, using a multichannel quantum-defect theory that we present here for ion-atom interactions. Such an efficient description is a key enabling element to understand few-body and many-body quantum systems involving ions. [ABSTRACT FROM AUTHOR]

We present an analytical description for ultracold collisions between two spin-1/2 fermions with isotropic spin-orbit coupling (SOC) of the Rashba type. We show that regardless of how weak the SOC may be, at sufficiently low energies the collision properties are significantly modified. The ubiquitous low energy Wigner threshold behavior is changed and its modified form for ground-state neutral atoms is given. The particles are further found to scatter preferentially into the lower-energy helicity states due to the breaking of parity conservation. This latter point establishes interaction with SOC as one mechanism for the spontaneous emergence of handedness. Our theory is applicable both to elementary spin-1/2 fermions such as electrons in condensed matter and to ultracold pseudo-spin-1/2 atoms such as 6Li in its ground hyperfine state. [ABSTRACT FROM AUTHOR]

The wide dissemination of images makes its protection problems urgent. Chaos theory is widely applied since it provides better solutions to image protection. This paper introduces a novel chaotic system that has line equilibrium points. Chaotic signals generated by chaotic systems are used in encryption and steganography to enhance security. Besides, the scrambling-diffusion encryption system is combined with the least significant bit (LSB)-pixel value differencing (PVD) steganography algorithm. The proposed algorithm process is reversible and the extracted image is lossless. And the whole system is designed and implemented on a field programmable gate array (FPGA), which improves the embedding efficiency and achieves high throughput while ensuring good image quality. [ABSTRACT FROM AUTHOR]

We observe Feshbach resonances in ultracold mixtures of 85Rb and 87Rb atoms in the 85Rb|2,+2〉+87Rb|1,+1〉 and 85Rb|2,-2〉+87Rb|1,-1〉 scattering channels. The positions and properties of the resonances are predicted and characterized using the semianalytic multichannel quantum-defect theory by Gao. Of particular interest, a number of broad entrance-channel-dominated p-wave resonances are identified, implicating exciting opportunities for studying a variety of p-wave interaction-dominated physics. [ABSTRACT FROM AUTHOR]