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Thanks to the porous structure, large specific surface area, and excellent electrical conductivity, three-dimensional porous nanofoams current collectors have attracted great interest in the field of energy storage devices. Herein, a facile, low cost, and one-step combustion synthesis is demonstrated to fabricate MnNi3O4/Ni nanofoams composites, and the composites can be directly converted into electrode by simple mechanical compression without the use of current collector, conductive agent, and binder, simplifying the manufacturing process. Due to the unique structure and morphology of Ni nanofoams, the composites electrodes exhibit high capacity and excellent cycle performance. At a rate of 1.44 mA cm−2, it can reach a high area specific capacity of 4.32 mAh cm−2 after 40 cycles. This work proves the superiority of the nanofoams structure, and provides a new way to construct binder-free electrodes for the field of energy storage and conversion.

In this work, we theoretically study the generation of circularly polarized XUV vortices from high harmonic generation driven by bicircular Laguerre-Gaussian (LG) fields with different frequency ratios, by using the strong-field approximation theory. Our simulation shows that the amplitude of the generated vortices from the ω-3ω bicircular LG field is about one order of magnitude larger than that from the ω-2ω field, irrespective of the harmonic order and the orbital angular momentum of the bicircular driving fields. Our analysis shows that the great increase of the vortex amplitude for the ω-3ω field originates from the harmonic enhancement of a single atom. Furthermore, in terms of quantum-orbit theory, the underlying physics of the harmonic enhancement of the single atom for the ω-3ω field is revealed. Our work provides a simple and robust method to increase the amplitude of the circularly polarized XUV vortices.

Facial recognition is one of the main research directions in the field of artificial intelligence and image processing. It has been widely used in identity authentication, video surveillance and biological detection. Because it is non-contact, natural, convenient and reliable, facial recognition has become a popular choice for biometric systems. The accuracy of facial recognition still needs to be improved, the main goal of this paper is to improve the accuracy of face recognition. Based on the support vector machine method, the focus is on the feature extraction and feature matching of face images. In view of the particularity of face images, the pre-processing of face images is studied. In this paper, grayscale normalization and geometric normalization pre-processing methods are used. In order to reduce the interference factors of the image as much as possible, the features are high-lighted, and the non-featured parts are weakened, this paper adopts the Histogram of Oriented Gradient feature extraction method. Then we proposed a new method based on SVM, which uses a one-to-many method to construct multiple SVM classifiers, selects the optimal parameters through repeated experiments, and selects ORL face database for testing. The recognition rate can reach about 98.5%.

Copper-catalyzed ortho-acyloxylation of the sp2 C–H bond of aryl amides with carboxylic acids is reported. Benzoic acids, cinnamic acids, and aliphatic acids can be involved, and the desired products were obtained in moderate to good yields. This procedure is compatible with a wide range of functional groups and heteroarenes without the use of any ligands or additives. This method provides an operationally simple approach for the synthesis of benzoate and cinnamate.

The tunable long wavelength lasers with durations below 30 fs and focusable peak intensities around 1014 W/cm2 provide an important parameter to control the the ionization process of molecules with structural complexity and multi-core nature, which can explore the potential applications such as imaging the molecular orbitals and probing nuclear dynamics with attosecond resolution. In this paper, experimental and theoretical investigations of the ionization of homo-nuclear diatomic molecules (i.e., O 2 and N 2 ) radiated by both linearly polarized (LP) and circularly polarized (CP) mid-infrared laser fields are reported. We find the ionization yields of O 2 exhibit an apparent gap between different wavelengths in LP fields, while the yield-gap becomes obscure in CP fields. In particular, the dependence of the yield-gap of N 2 between different wavelengths on the laser polarization is in contrast to that of O 2 . With the help of the S-matrix theory, the peculiar polarization-dependent yield-gaps can be attributed to both the molecular orbital and the two-center interference effect in molecular ionization process. Our findings provide a new insight into the molecular ionization process and retrieving the information of the molecular structure.

Hydrofunctionalization of trifluoromethyl alkenes is highly challenging, because the nucleophilic addition is oftentimes followed by β-F elimination in this case. By the use of tetrabutylammonium decatungstate (TBADT) as a hydrogen-atom-transfer (HAT) photocatalyst for acyl C–H activation, we successfully avoid the β-F elimination in the hydroacylation of trifluoromethyl alkenes with aldehydes. This light (390 nm) promoted reaction provides a facile and efficient access to various β-CF3 ketones in complete regiocontrol with high functionality tolerance and 100% atom economy.

Unactivated alkyl chlorides are abundant building blocks in organic synthesis, but they have been rarely engaged in cross-electrophile coupling. Herein, we report a Ni/Ti-cocatalyzed reductive allylic defluorinative cross-coupling between trifluoromethyl alkenes and unactivated alkyl chlorides and bromides, enabling the efficient preparation of diverse functional-group-rich gem-difluoroalkenes. Notably, synthesis of the gem-difluoroalkene analogues of azaperone, haloperidol, and benperidol was also accomplished using our method as a key step.

Self-healing concrete designs can protect against deterioration and improve durability. However, there is no unified conclusion regarding the effective preparation and mechanical properties of self-healing concrete. In this paper, microcapsules are used in cement-based materials, the reasonable dosage of microcapsules is determined, and the self-healing performance of the microcapsule self-healing system under different curing agents is explored. The microcapsules and curing agent are shown to enhance the flexural and compressive strength of mortar specimens at relatively low contents. The optimal microcapsule content in terms of compressive strength is 1–3%. When the content of the microcapsule reaches 7%, the strength of the specimen decreases by approximately 30%. Sodium fluorosilicate is better-suited to the microcapsule self-healing cement-based system than the other two fluorosilicates, potassium fluorosilicate and magnesium, which have similarly poor healing performance as curing agents. Healing time also appears to significantly influence the microcapsule self-healing system, mortar specimens that healed for 28 days are significantly higher than those that healed for 7 days. This work may provide a valuable reference for the design and preparation of self-healing cementitious composite structures.

Model-Driven Engineering (MDE) tries to reduce the effort spent on software development by generating codes from models. People concentrate their minds on the transformation between models and models, or between models and codes. People also concentrate on checking consistency between different models such as consistency between a class diagram and a sequence diagram and consistency between a sequence diagram and a state machine diagram. Checking relationship consistency and class redundancy in a class model is still important but ignored in recent years. This paper concentrates on relationship problems between classes in a class diagram and proposes methods of checking various relationship problems. We address the redundancy of a class’s operations and attributes. We identify a large range of the problems for class diagram. Our research is based on the relationship abstraction rules.

We originally present a linearly polarized Raman radiation emitted from an actively Q-switched Nd:YAG/YVO4 laser. An 1175.25 nm Raman output was achieved using a uniaxial a-cut YVO4 crystal in a Z-shape laser cavity. The stable Raman power of 1.8 W was obtained, corresponding conversion efficiency of 8.8% from 1064 nm to 1175 nm. The Raman radiation with a polarization extinction ratio of 10.4-dB was observed for the first time. Our experimental results demonstrate that the asymmetrical Raman crystal gain can result in a uniform linear polarization and permit emitting orthogonal polarization radiation in a cascaded Raman laser.

The effects of natural disasters on capital markets have been investigated by limited evidence even though these calamities bring considerable damages or loss of life. To fill this gap, we investigate the impacts of natural disasters, particularly earthquakes, on security analysts' earnings forecasts for affected firms in China. We obtain three key findings. First, analysts' optimism significantly decreases for firms located in neighborhood areas. Second, earthquakes do not significantly affect firm earnings and stock returns, thereby indicating that post-earthquake analyst pessimism is not based on rational judgment. Third, media attention promotes irrational pessimism among analysts, and post-earthquake pessimism is a result of heuristics bias attributable to psychological shocks. However, analysts correct the bias after initial irrational forecasts. Taken together, our findings contribute to the broader psychology and economics literature on the effects of natural disasters on analyst forecasts.

Cu2Se nanoflake arrays supported by Cu foams are synthesized by a facile hydrothermal method in this study. The Cu2Se materials are directly used as an anode for lithium ion batteries, which show superior cycle performance with significant capacity increase. Combining with previous reports and scanning electron microscope images after cycling, the capacity increase caused by the reversible growth of a polymeric film is discussed. Electrochemical impedance spectroscopy is used to test the reversible growth of the polymeric film. By analyzing the three-dimensional Nyquist plots at different potentials during the discharge/charge process, detailed electrochemical reaction information can be obtained, which can further verify the reversible formation of a polymeric film at low potential.

An efficient copper-catalyzed direct o-acyloxylation of 2-phenylpyridine with carboxylic acids using oxygen as the oxidant has been developed. Various acids including aromatic acids, cinnamic acids and aliphatic acids are effective acyloxylation reagents and provide the desired products in moderate to excellent yields. The reaction proceeds well under an oxygen atmosphere, making this method potentially practical.

The experimentally observed pronounced mid-infrared wavelength-dependent angular distributions (ADs)of low-energy electrons is attributed to the non-adiabatic effect by restoring to an improved semi-classical model.

On site construction process such as concreting usually follow a standard process, the degree of process proficiency will impact the construction quality directly. So it is very important and necessary to educate students who will become the construction manager on construction process before starting their onsite construction work. Previous construction learning is apart from classroom and construction site, it is hard for students to image and know the steps of construction process. Nowadays 3D game-based process learning becomes a great tool in engineering education, which can solve this problem effectively. This paper presents a game-based concreting process course to educate 60 junior students majoring in civil engineering. Its objectives are 3 folds: (1) to develop the specific game simulation of concreting process; (2) to design an easy recognized Graphical User Interface (GUI) for students; (3) to ensure good memories of students after learning. Final results of this game-based construction process learning course are fully illustrated.

Enterovirus 71 (EV71) is one of the main etiological agents of the Hand, Foot and Mouth Disease (HFMD) and has been known to cause fatal neurological complications such as herpangina, aseptic meningitis, poliomyelitis-like paralysis and encephalitis. EV71 is endemic in the Asia-Pacific region and causes occasional epidemics. In order to better understand EV71 infection, we compared the proteome between EV71-susceptible and EV71-resistant human Rhabdomyosarcoma (RD) cell line. We found significant differences in the β-actin variants between the EV71-susceptible RD cells and EV71-resistant RD cells, suggesting that β-actin, in association with other proteins such as annexin 2 is required in vesicular transport of EV71. This finding further support our previous study that actin potentially plays a role in pathogenesis and the establishment of the disease in HFMD.

We perform an experimental study on comparison between the ionization of homonuclear diatomic molecules (O-2 and N-2) and their companion atoms (Xe and Ar) radiated by circularly polarized intense laser fields. We find that the ionization of O-2 shows suppression with respect to its companion atom Xe, which exhibits a clear wavelength and intensity dependence similar to that in linearly polarized laser field, while the ionization of N-2 behaves like its companion atom Ar. With the help of S-matrix theoretical analysis, our observations can be attributed to both the molecular orbital and the two-center interference effect in molecular ionization process.

Growth of the virulent human malaria parasite Plasmodium falciparum is dependent on an extracellular supply of pantothenate (vitamin B(5)) and is susceptible to inhibition by pantothenate analogues that hinder pantothenate utilization. In this study, on the hunt for pantothenate analogues with increased potency relative to those reported previously, we screened a series of pantothenamides (amide analogues of pantothenate) against P. falciparum and show for the first time that analogues of this type possess antiplasmodial activity. Although the active pantothenamides in this series exhibit only modest potency under standard in vitro culture conditions, we show that the potency of pantothenamides is selectively enhanced when the parasite culture medium is pre-incubated at 37°C for a prolonged period. We present evidence that this finding is linked to the presence in Albumax II (a serum-substitute routinely used for in vitro cultivation of P. falciparum) of pantetheinase activity: the activity of an enzyme that hydrolyzes the pantothenate metabolite pantetheine, for which pantothenamides also serve as substrates. Pantetheinase activity, and thereby pantothenamide degradation, is reduced following incubation of Albumax II-containing culture medium for a prolonged period at 37°C, revealing the true, sub-micromolar potency of pantothenamides. Importantly we show that the potent antiplasmodial effect of pantothenamides is attenuated with pantothenate, consistent with the compounds inhibiting parasite proliferation specifically by inhibiting pantothenate and/or CoA utilization. Additionally, we show that the pantothenamides interact with P. falciparum pantothenate kinase, the first enzyme involved in converting pantothenate to coenzyme A. This is the first demonstration of on-target antiplasmodial pantothenate analogues with sub-micromolar potency, and highlights the potential of pantetheinase-resistant pantothenamides as antimalarial agents.

Diatomic molecules (e.g., O(2)) in an intense laser field exhibit a peculiar suppressed ionization behavior compared to their companion atoms. Several physical models have been proposed to account for this suppression, while no consensus has been achieved. In this Letter, we aim to clarify the underlying mechanisms behind this molecular ionization suppression. Experimental data recorded at midinfrared laser wavelength and its comparison with that at near-infrared wavelength revealed a peculiar wavelength and intensity dependence of the suppressed ionization of O(2) with respect to its companion atom of Xe, while N(2) behaves like a structureless atom. It is found that the S-matrix theory calculation can reproduce well the experimental observations and unambiguously identifies the significant role of two-center interference effect in the ionization suppression of O(2).

We present experimental and theoretical evidence on the breakdown of the simple man's model in the high-energy recollision region by examining both the energy-resolved angular distribution of photoelectrons in above-threshold ionization and the spectrum of high-order harmonics generated in elliptically polarized driver fields. With the help of a semiclassical model calculation, we show that, surprisingly, even for the high-energy recollision electrons, their wave-packet dynamics can be influenced strongly by the Coulomb field.

There are limitations of studies on team building from different perspectives. The conclusions of relations between the internal processes, boundary-spanning activities, cohesion and effectiveness are contradictory in those studies. A survey was used to collect relevant data for study of these issues. Path analyses were conducted for hypothesis testing. There are some conclusions as follow: First, inward-facing boundary management has a significant effect on outward-facing boundary management, which means the mutual supportive and synergic relation between them. Second, inward-facing boundary management has a significant effect on cohesion and attitudes, and the mediating roles of team cohesion to the relationship between inward-facing boundary management and team attitudes are supported. Third, the assumption on relationships between outward-facing boundary management, cohesion and attitudes is supported partially.

Today most news pages are generated from some underlying structured source, so we think that template-dependent wrappers should be more suitable for them than template-independent wrappers. In this paper, we propose a novel automatic template-dependent Web news content extraction approach based on similar pages. Firstly, We choose two similar pages as training samples and represent them as two HTML DOM trees. Secondly, we create the maximum matching tree between the DOM trees using our simple tree matching and backtracking algorithm. Then, by analyzing the characteristics of nodes in the maximum matching tree, we eliminate the noise nodes to generate an extraction template. Finally, we build a template-dependent wrapper for target news pages whose structures are similar to the samples. Experimental results indicate that our approach is effective and efficient for Web news content extraction, and the average harmonic mean of precision and recall reaches 98.3% .

We present energy-resolved angular distributions of photoelectrons generated in above-threshold ionization (ATI) of nonaligned diatomic molecules N2 and O2 in high-intensity short laser pulses, with emphasis on the most energetic part of the spectra. The angular distribution for photoelectrons with energy of 10Up (Up: ponderomotive energy), i.e., the plateau cutoff in ATI spectra, is found to be broader in O2 than in N2. Resorting to the analyses from both an S-matrix theory and an intuitive semiclassical model, we attribute the observation to the effect of the ground state molecular orbital structure on high-energy electron emission in strong-field molecular ionization. PACS numbers: 33.80.Rv, 33.80.Wz, 42.50.Hz When an atom or molecule interacts with an optical field of peak intensity around 10 14 W=cm 2 , the outmost electron is first tunnel ionized, accelerated in the oscillating electric field of the laser, and may be driven back to its parent ion. This recolliding process, being the core ingredient of the rescattering scenario [1], has initiated many interesting laser-induced phenomena. Among them, imaging the dynamics of complex molecules with the help of the recolliding electron current, has attracted a lot of attention in the strong-field physics community [2]. Recently, it was reported that the outmost molecular orbital of the N2 molecule can be extracted from the high-order harmonic generation spectra using the tomographic procedure [3]. Therein, structural information of the molecule may be extracted from the recombination process of the recolliding

We present high resolution photoelectron energy spectra of noble gas atoms from high intensity above-threshold ionization (ATI) at midinfrared wavelengths. An unexpected structure at the very low-energy portion of the spectra, in striking contrast to the prediction of the simple-man theory, has been revealed. A semiclassical model calculation is able to reproduce the experimental feature and suggests the prominent role of the Coulomb interaction of the outgoing electron with the parent ion in producing the peculiar structure in long wavelength ATI spectra.

This chapter focuses on China’s e-government practices. Compared to other world economic powers, the Chinese government has been slow in adopting the Internet technology in carrying out its administrative and public service functions. As China’s Information technology infrastructure improves and its Internet user population continues to grow, however, the government has become increasingly convinced by the significance and benefits of conducting its business online. The chapter reviews the evolution of e-government in China, examines its current status, identifies the unique problems and challenges China faces, and highlights recent Chinese government initiatives that promise to dramatically change China’s e-government landscape.