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We study the photon energy sharing between the photoelectron and the nuclei in the process of above-threshold multiphoton dissociative ionization of CO molecules by measuring the joint energy spectra. The experimental observation shows that the electron-nuclear energy sharing strongly depends on the vibrational state. The experimental observation shows that both the energy deposited to the nuclei of $\mathrm{C}{\mathrm{O}}^{+}$ and the emitted photoelectron decrease with increasing the vibrational level. Through studying the vibrationally resolved nuclear kinetic energy release and photoelectron energy spectra at different laser intensities, for each vibrational level of $\mathrm{C}{\mathrm{O}}^{+}$, the nuclei always tend to take the same amount of energy in every vibrational level regardless of the laser intensity, while the energy deposited to the photoelectron varies with respect to the laser intensity because of the ponderomotive shifted energy and the distinct dissociative ionization mechanisms.

Combining the partial-Fourier-transform approach with Wenzel-Kramers-Brillouin approximation, we theoretically study the strong-field tunneling ionization of diatomic and polyatomic molecules. First we obtain the analytical expression of momentum distribution at the tunnel exit of diatomic molecules, and then we calculate the alignment-dependent ionization rate at different laser intensities and internuclear distances. We show that the internuclear distance has a significant effect on the alignment dependence of the ionization rate. Using this approach, we can also separate the contributions of each atomic center and show the interference effect between them. Finally, we extend this method to a polyatomic molecule, benzene, as an example.

We study the phase structure of the tunneling wave packets from strong-field ionization of molecules and present a molecular quantum-trajectory Monte Carlo model to describe the laser-driven dynamics of photoelectron momentum distributions of molecules. Using our model, we reproduce and explain the alignment-dependent molecular frame photoelectron spectra of strong-field tunneling ionization of N_{2} reported by M. Meckel et al. [Nat. Phys. 10, 594 (2014)]. In addition to modeling the low-energy photoelectron angular distributions quantitatively, we extract the phase structure of strong-field molecular tunneling wave packets, shedding light on its physical origin. The initial phase of the tunneling wave packets at the tunnel exit depends on both the initial transverse momentum distribution and the molecular internuclear distance. We further show that the ionizing molecular orbital has a critical effect on the initial phase of the tunneling wave packets. The phase structure of the photoelectron wave packet is a key ingredient for modeling strong-field molecular photoelectron holography, high-harmonic generation, and molecular orbital imaging.

Spontaneous combustion of coal is a serious threat to the normal working of the mine and the safety of miners, the research to prevent spontaneous combustion of coal has a great significance. Technology based on the three-phase bubble theory, combined with characteristics of coal of 7312-2 caving face of a coal mine in Xuzhou, using laboratory studies to determination the fly ash , Wong and a variety of surfactant , then determining the formula of three-phase foam which is fit for a coal mine coal, it can restrain goal spontaneous combustion effectively and beneficial to safety production and environmental prevention.

Common feature based pharmacophore and structure-based docking approaches have been employed in the identification of novel anti-HCV candidates from our in-house database. A total of 31 hits identified in silico were screened in vitro assay. 20 Compounds demonstrated anti-HCV activities (EC(50)50 μM), including two naturally occurring flavones apigenin (21) and luteolin (22) with low micromole EC(50) values and three compounds (23, 24 and 25) of novel scaffolds with moderate potencies. In addition, pharmacophore refinement was also conducted based on the current knowledge of flavone-derived anti-HCV candidates and the results of combined in silico and in vitro assays.

Solid-phase microextraction (SPME) coupled to gas chromatography (GC) has been developed for the analysis of naphthalene residues in five textiles samples using sol-gel-derived 5,11,17,23-tetra-tert-butyl-25,27-dihydroxy-26,28diglycidyloxycalix[4]arene/hydroxy-terminated silicone oil fiber. The main parameters affecting extraction and desorption process such as temperature and time were optimized statistically. Compared with four commercial stationary phases and sol-gelderived OH-TSO SPME fiber, this fiber showed statistically highest enrichment capability for naphthalene in the textile sample. SPME‐GC‐flame ionization detection method showed good linearity for the tested concentration range with regression coefficient being 0.9996. Detection limits was 1.17 ng/g. Relative standard deviations ( n = 6) of method at three concentration levels of 1.0, 0.5, and 0.1 µg/g ranged between 1.1% and 5.4%, which provided good analytical precision. In addition, this fiber had satisfying fiber to fiber and batch to batch reproducibility. Recoveries for the analyte ranged from 78.3% to 102.7%. It indicated that this method developed was an efficient and accurate procedure for determination of naphthalene residues in textiles samples.

3-Hydroxybutyrate methyl ester (HBME) was prepared from hydrolysis of bacterial poly-3-hydroxybutyrate (PHB) using methanol as an esterification agent in the presence of sulfuric acid. Physicochemical and fuel related properties of HBME were studied for the possibility of using HBME as a gasoline additive. When HBME was blended with 97# gasoline in volume ratios of 5%, 8.5%, 10%, 15% and 20%, respectively, it was found that HBME had similar or better properties as a fuel additive compared with ethanol in terms of oxygen content, dynamic viscosity, flash point and boiling point. The blending of HBME and gasoline showed only little difference compared with the 97# gasoline in terms of octane number (RON) and distillation ranges, especially for the HBME 8.5% and 10% blends, which demonstrated an over 93% combustion heat of gasoline with less than 5% reduction in RON.

MADS-box transcription factors are important for plant growth and development, and hundreds of MADS-box genes have been functionally characterized in plants. However, less is known about the functions of these genes in the economically important allopolyploid oil crop, Brassica napus. We identified 307 potential MADS-box genes (BnMADSs) in the B. napus genome and categorized them into type I (Mα, Mβ, and Mγ) and type II (MADS DNA-binding domain, intervening domain, keratin-like domain, and C-terminal domain [MIKC]c and MIKC*) based on phylogeny, protein motif structure, and exon-intron organization. We identified one conserved intron pattern in the MADS-box domain and seven conserved intron patterns in the K-box domain of the MIKCc genes that were previously ignored and may be associated with function. Chromosome distribution and synteny analysis revealed that hybridization between Brassica rapa and Brassica oleracea, segmental duplication, and homologous exchange (HE) in B. napus were the main BnMADSs expansion mechanisms. Promoter cis-element analyses indicated that BnMADSs may respond to various stressors (drought, heat, hormones) and light. Expression analyses showed that homologous genes in a given subfamily or sister pair are highly conserved, indicating widespread functional conservation and redundancy. Analyses of BnMADSs provide a basis for understanding their functional roles in plant development.

We present a subcycle nonadiabatic strong-field tunneling theory and derive the position of tunnel exit, the transverse and longitudinal momentum distributions at the tunnel exit, and the ionization rate in an instantaneous laser field. These tunneling coordinates are shown to nonadiabatically couple with each other in an instantaneous laser field when the electron tunnels through the barrier. We have further incorporated the nonadiabatic tunneling theory with the quantum-trajectory Monte Carlo approach to investigate the nonadiabatic effect on the photoelectron angular distributions. The simulated photoelectron angular distributions with the nonadiabatic corrections have been validated by comparison with the ab initio results through numerically solving the time-dependent Schr\"odinger equation. The nonadiabatic coordinates at the tunnel exit play important roles in both the direct ionization and rescattering process. The nonadiabatic tunneling theory provides an intuitive understanding on subcycle dynamics of tunneling ionization.

A home-made sol-gel-derived co-poly (hydroxy-terminated silicone divinylbenzene) (OH-TSO/DVB) coating fiber has firstly been applied for headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography (GC)—nitrogen-phosphorus detector (NPD) to determine five organophosphorus pesticides (OPPs) in pakchoi samples. The following parameters influencing on the extraction efficiency of HS-SPME were optimized statistically: extraction temperature, extraction time, ionic strength, constant agitation, effect of sample matrix, desorption temperature, and desorption time. Compared with commercial available fibers and OH-TSO SPME fiber, this fiber showed statistically better enrichment capability for these pesticides. For the developed HS-SPME-GC method, it was found that the linearity was all two orders of magnitude, with the limits of detection (LOD) ranging from 0.007 to 0.07 ng g−1, and relative standard deviations (RSD) varying between 4.1 and 8.7% (n = 5). Recoveries of spiked pakchoi samples ranged from 80.74 to 101.47% for every pesticide at each investigated concentration. Overall, it indicated that the obtained method is a validated and accurate procedure for determination of OPPs in pakchoi samples.

We theoretically study the control of the interferences of multiple tunneling photoelectron wave packets in both temporal and spatial domains by an orthogonally polarized two-color laser pulse. Profound carpetlike and stripelike interference patterns can be turned on or off in the momentum spectra using a weak streaking field at half the frequency of a strong fundamental field. The modulations of the interference patterns with respect to the relative phase between the two frequency components are well recaptured by both a semiclassical interference model and an ab initio simulation with numerically solving the time-dependent Schr\"odinger equation. We highlight the importance of the ionic Coulomb potential on the photoelectron angular distributions of atoms in the orthogonally polarized two-color pulses. It is shown that the interference induced by the forward rescattering trajectories is enhanced while the contribution of the direct trajectories is suppressed. This study offers alternative routes toward probing and controlling the ultrafast ionization dynamics of atoms and molecules.

We measure photoelectron energy distributions from single ionization of xenon atoms by a linearly polarized laser pulse $(800\phantom{\rule{0.16em}{0ex}}\mathrm{nm},\phantom{\rule{0.28em}{0ex}}25\phantom{\rule{0.16em}{0ex}}\mathrm{fs})$ with successively varying the laser intensity within the region of $1.4\ensuremath{-}7.0\ifmmode\times\else\texttimes\fi{}{10}^{13}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/\mathrm{c}{\mathrm{m}}^{2}$. By measuring the photoelectron energy shifted with the ponderomotive potential, we have calibrated the laser peak intensity precisely with an uncertainty less than $5%$. Employing the quantum trajectory Monte Carlo theory, we simulate the photoelectron energy spectra with respect to the laser intensity. By comparison between the measurement and the simulation, we are able to identify resonant structures from photoelectron energy spectra in the low-energy region, which do not shift with the laser intensity. Inspecting the momentum distribution along the laser propagation axis, we have further shown that the quantum interference effect has a significant effect on the width of the momentum distribution perpendicular to the laser polarization direction beside the Coulomb focusing effect.

Absolute deviation is utilized as a measure of risk and a new function is provided for it. We consider the mean-absolute deviation (MAD) portfolio optimization problem in a frictional market with additional constraints representing the so-called short sales. An algorithm for solving the optimization problem is thus presented, which uses the special structure of the original problem to reduce to a linear programming. The numerical test shows the validity of the method.

We measure the wavelength-dependent correlated-electron momentum (CEM) spectra of strong-field double ionization of Xe atoms, and observe a significant change from a roughly nonstructured (uncorrelated) pattern at 795 nm to an elongated distribution with V-shaped structure (correlated) at higher wavelengths of 1320 and 1810 nm, pointing to the transition of the ionization dynamics imprinted in the momentum distributions. These observations are well reproduced by a semiclassical model using Green–Sellin–Zachor potential to take into account the screening effect. We show that the momentum distribution of Xe2+ undergoes a bifurcation structure emerging from single-hump to double-hump structure as the laser wavelength increases, which is dramatically different from that of He2+, indicating the complex multi-electron effect. By back analyzing the double ionization trajectories in the phase space (the initial transverse momentum and the laser phase at the tunneling exit) of the first tunneled electrons, we provide deep insight into the physical origin for electron correlation dynamics. We find that a random distribution in phase-space is responsible for a less distinct structured CEM spectrum at shorter wavelength. While increasing the laser wavelength, a topology-invariant pattern in phase-space appears, leading to the clearly visible V-shaped structures.

We study the strong-field tunneling ionization of molecules using the molecular quantum trajectory Monte-Carlo model and the partial Fourier-transform approach for molecules. From both models, we extract the phase structure of the tunneling wave packet of aligned molecules, which depends on the initial transverse momentum. We extend the partial Fourier-transform approach to calculate the photoelectron momentum distributions of diatomic molecules. We further calculate the alignment-dependent ionization rates by both models. These semiclassical models for strong-field ionization of molecules are particularly useful in the study of photoelectron diffraction and photoelectron holography.

The first, stereospecific, and elegant synthesis of the natural product (+)-Carainterol A was developed by using the Robinson annulation reaction as a key step to build the eudesmane sketeton.

The sorption and desorption characteristics of four kinds of organic phosphorus with different molecular structures (glycerophosphate (GP), glucose-6-phosphate (G6P), adenosine triphosphate (ATP), and myo-inositol hexakisphosphate (IHP)) on three kinds of aluminum (oxyhydr)oxides (amorphous Al(OH)3, boehmite, and alpha-Al2O3) were studied. The underlying mechanisms were also illustrated. Results showed that the maximum sorption amounts of OP onto Al (oxyhydr)oxides, on a per gram dry weight basis, decreased as following: amorphous Al(OH)3boehmitealpha-Al2O3. This mainly related to the mineral crystallinity and surface heterogeneity. With the exception of sorption of IHP on amorphous Al (OH)3, the maximum sorption density decreased with increasing molecular weight (MW) of OP, following the order: GPG6PATPIHP. However, the sorption amount of IHP on amorphous Al (OH)3 was much higher than those of other OP, due to the transformation of surface complexes of IHP to surface precipitation and thus enhancing the sorption. The sorption kinetics results showed that sorption of OP underwent the first onset rapid sorption, i. e. a certain amount of sorption occurred within an onset extremely short period, and a following long and slow sorption process. Amorphous Al (OH)3 had the greatest onset rapid sorption density, and the onset rapid sorption density of OP on Al (oxyhydr) oxides decreased with increasing MW. Desorption capacities of OP by KCl and citrate solutions related to the surface affinity between OP and boehmite. Initial desorption percentages by KCl decreased in the order: G6P (10.53%)GP(6.91%)ATP (3.06%)IHP (0.8%). The maximum desorption percentages of OP by citrate were 4-5 times greater than those by KCl. During resorption process of P by KCl, the maximum desorption rate achieved after a fast desorption in a few hours, followed by diffusion-resorption during which the desorption percentage gradually decreased. Specially, both diffusion-resorption and surface precipitation promoted the resorption of IHP on mineral surface. Conclusively, the strong specific sorption of OP occurs on the surface of Al (oxyhydr) oxides, and molecular structure and size of OP as well as the crystallinity and crystal structure of minerals are the key factors affecting the interfacial reactions and environmental behaviors of OP.

One key technology of laser active jamming effect is that the jamming laser is accurately controlled to reach laser seeker ahead of the target indicating laser. And it is sure that the jamming laser must be in the gate of laser seeker. In this paper, many factors are synthetically considered such as the gate of laser seeker, the jitter time of guiding laser, the jitter time of jamming laser, the optical path difference revising time of jamming laser and so on. And a probability model is put forward that the jamming laser reach laser seeker ahead of the target indicating laser. A simulating experiment is done, and the optimum ahead time range is gotten.

Thyroid peroxidase (TPO) is an important autoantigen in Hashimoto's thyroiditis (HT), and almost all epitopes are located in TPO ectodomain. The glycosylation of TPO might contribute to breaking self-tolerance, therefore, purified glycosylated recombinant TPO ectodomain is prerequisite of elucidating its role in the pathogenesis of HT. The aim of our study was to investigate whether the glycosylation has influence on the antigenic determinants of recombinant TPO.Bac-to-Bac baculovirus expression system was used to generate recombinant human TPO ectodomain. The antigenicity was analyzed by antigen specific enzyme-linked immunosorbant assays (ELISAs). The glycosylation of recombinant human TPO ectodomain of High Five insect cell origin was detected by lectin-ELISAs.TPO ectodomain was recovered from the culture media as a soluble protein, and it was fused with a hexahistidine tag which allowed purification by nickel-affinity chromatography. The recombinant TPO ectodomain could be recognized by all the 54 HT patients and three TPO monoclonal antibodies. Fucose, sialic acid and galactose were all detected on the recombinant TPO ectodomain. Sera TPOAb binding decreased slightly after non-specific deglycosylation of TPO by periodic acid.High Five insect cells derived recombinant human TPO ectodomain had N-glycosylation sites, which might have little effect on recognition by serum TPOAb.

A series of diketo tetrazoles and diketo triazoles were designed and synthesized as bioisosteres of α,γ-diketo acid, the active site inhibitor of HCV (Hepatitis C virus) polymerase NS5B. Among the synthesized compounds, 4-(4-fluorobenzyloxy)phenyl diketo triazole (30) exhibited anti-HCV activity with an EC50 value of 3.9 μM and an SI value more than 128. The reduction of viral protein and mRNA levels were also validated, supporting the anti-HCV activity of compound 30. These results provide convincing evidence that the diketo tetrazoles and diketo triazoles can be developed as bioisosteres of α,γ-diketo acid to exhibit potent inhibitory activity against HCV.

In the title molecule, C28H28O9, the phenol and the benzene rings adjacent to the α,β-unsaturated ketone unit are inclined at 9.15 (13)° to each other. The terminal phenyl ring is oriented with respect to the phenol ring at a dihedral angle of 85.88 (13)°. In the crystal, the methylene C atoms of the dihydrodioxine ring are disordered over two sites with an occupancy ratio of 0.463 (18):0.537 (18), and both disordered components of the dihydrodioxine ring adopt twisted-chair conformations. An intramolecular O—H...O hydrogen bond and weak intermolecular C—H...O hydrogen bonds are present in the crystal structure.

The first, stereospecific, and elegant synthesis of the natural product (+)-Carainterol A was developed by using the Robinson annulation reaction as a key step to build the eudesmane sketeton.

To investigate insulin resistance in type 1 diabetes (T1DM) with euglycemic-hyperinsulinemic clamp.Eight cases of newly diagnosed T1DM and 8 cases of newly diagnosed type 2 diabetes (T2DM) were selected. Their insulin sensitivity index (ISI) was evaluated with euglycemic-hyperinsulinemic clamp after 2 week insulin intensive treatment and compared with that of 10 healthy volunteers (normal control group, NC group).Age, BMI, fasting insulin (FIns), fasting C-peptide in the T1DM group were significantly lower than those in the NC group, while waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), TC, TG, LDL-C, HDL-C were not significantly different between the T1DM and NC groups. Age, BMI, WHR, FIns, fasting C-peptide, SBP, TC, TG in the T1DM group were significantly lower than those in the T2DM group. The ISI of the NC, T1DM and T2DM groups were 12. 83 +/- 1.09, 9.95 +/-0.50, 3.80 +/- 0.20, respectively. There was significant difference among the three groups (P0.05).The ISI in T1DM was significantly lower than that in NC group, but higher than that in T2DM.

Though the re-understanding of methods that enterprises used in value achieving, enterprise equity and enterprise consciousness are put forward to investigate the enterprise's Macro-development strategy, therefore, an analytic model of Macro-development in enterprise's value achieving is established. Through the quantitative analysis of the model, a score standard of enterprise or the excellence ones in the industry is established. Though the empirical research, the model is testified as well manipulation, it is can also help managers to implement the strategy appropriately on the basis of analyzing the enterprise.

EMG signals of dynamically contracting muscle have never been used to predict experimentally known muscle forces across subjects. Here, we use an artificial neural network (ANN) approach to first derive an EMG-force relationship from a subset of experimentally determined EMGs and muscle forces; second, we use this relationship to predict individual muscle forces for different contractile conditions and in subjects whose EMG and force data were not used in the derivation of the EMG-force relationship; and third, we validate the predicted muscle forces against the known forces recorded in vivo. EMG and muscle forces were recorded from the cat soleus for a variety of locomotor conditions giving a data base from three subjects, four locomotor conditions, and 8-16 steps per subject and condition. Considering the conceptual differences in the tasks investigated (e.g. slow walking vs. trotting), the intra-subject results obtained here are superior to those published previously, even though the approach did not require a muscle model or the instantaneous contractile conditions as input for the force predictions. The inter-subject results are the first of this kind to be presented in the literature and they typically gave cross-correlation coefficients between actual and predicted forces of >0.90 and root mean square errors of

In this paper a multivariable generalized predictive adaptive control(MGPC) scheme is presented under the multi step cost-function with the polynomial matrix weighting. A simplified MGPC adaptive algorithm and a comparison between the simplified algorithm and original one in the amount of calculation are also given.