A new method for the alkali catalytic modification of lignite in subcritical H2O–CO systems is presented, which can greatly improve its caking properties (caking index, >90). Soxhlet extraction ...technology coupled with GPC (gel permeation chromatography), FTIR (Fourier transform infrared spectroscopy), and 13C-NMR (carbon-13 nuclear magnetic resonance) analysis methods were used to investigate the structural evolution and formation mechanisms of solutes of n-hexane, benzene, and tetrahydrofuran in modified coal (denoted as NS, BS, and TS, respectively), which were the main caking components in the modified lignite. The results showed that the solutes were composed of four kinds of compounds with weight-average molecular weights in the range of 1170–2900, 300–550, 190–300, and 100–150, respectively. Oxygen-containing functional groups appeared in many forms, such as phenolic OH, aliphatic OH, ether bonds, and carbonyl and carboxyl groups, but mainly existed as C–O. When the temperature was <320 °C, NS consisted of aliphatic ring compounds, while BS and TS contained some aromatics, with an average of two aromatic rings per cluster in both. The appearance of monocyclic aromatic structures in the solutes occurred in the 320–330 °C temperature range, with one to three aromatic rings in the BS clusters, while polycyclic aromatic structures with more than five rings appeared in TS. The statistical structural models of the solutes all contained polycyclic aliphatic/aromatic structures as their main bodies, connected with substituents such as monocyclic aromatic structures, aliphatic side chains, and oxygen-containing functional groups. They are consistent with the structure of caking components in caking coal. The formation of caking components in modified lignite therefore underwent four distinct stages: separation of primary solutes, formation of pyrolysis solutes, formation of hydrogenated solutes, and formation of polycondensation solutes. This study provides valuable insights into the caking transition of modified coal and a basis for the high-added value utilization of lignite.
Propolis has a broad spectrum of biological activities; however, whether its essential oils have neuroprotective effects is unknown. In this study, we found that propolis essential oil (PEO) could ...significantly reverse the anxiety-like behavior of restraint-stressed mice, and has no effect on locomotor activity. Furthermore, PEO significantly decreased the plasma levels of cortisol (CORT), adrenocorticotropic hormone (ACTH) and malondialdehyde (MDA), whereas it increased the activity of superoxide dismutase (SOD) in restraint-stressed mice. These results strongly suggest that PEO has therapeutic effects on anxiety through antagonizing the hyperfunction of hypothalamic–pituitary–adrenal (HPA) axis and improving the ability of antioxidation in brain tissue.
To evaluate the effectiveness of AIDS intervention programs on men aged 50 or over and having had non-marital sexual behavior.
A community-based intervention/experimental and based on individual ...level study was adopted. Stratified sampling method was used. 12 townships/streets in Fuyang district of Hangzhou were identified as intervention or control group (six research sites each). All of the subjects in the township (street) were included. The inclusion criteria of study objects would include men aged 50 or older who reported having unmarried sex in the last year. Estimated sample size was 290, with each 145 in the intervention group and the control group. All the intervention group participants were provided with a total of 4 intervention-related items (knowledge and education on AIDS prevention, information radiation and behavioral change, broadcast expert lectures), every 3 months, for 12 month, the main evaluation indicators would include: incidence of non-marital sex and commercial sex in the last year,
In this study, the density distributions of large nuclei are typically modeled with a Woods–Saxon distribution characterized by a radius R0 and skin depth a. Deformation parameters β are then ...introduced to describe non-spherical nuclei using an expansion in spherical harmonics R0(1+β2Y20+β4Y40). But when a nucleus is non-spherical, the R0 and a inferred from electron scattering experiments that integrate over all nuclear orientations cannot be used directly as the parameters in the Woods–Saxon distribution. In addition, the β2 values typically derived from the reduced electric quadrupole transition probability B(E2)↑ are not directly related to the β2 values used in the spherical harmonic expansion. B(E2)↑ is more accurately related to the intrinsic quadrupole moment Q0 than to β2. One can however calculate Q0 for a given β2 and then derive B(E2)↑ from Q0. In this paper we calculate and tabulate the R0, a , and β2 values that when used in a Woods–Saxon distribution, will give results consistent with electron scattering data. We then present calculations of the second and third harmonic participant eccentricity (ε2 and ε3) with the new and old parameters. We demonstrate that ε3 is particularly sensitive to a and argue that using the incorrect value of a has important implications for the extraction of viscosity to entropy ratio (η/s) from the QGP created in Heavy Ion collisions.
We examined a possible association between HLA-A and -B polymorphisms and susceptibility to Henoch-Schönlein purpura (HSP) in Han and Mongolian children in Inner Mongolia, through a case-control ...study. Two hundred and sixty-eight unrelated children were enrolled, including 56 Mongolian and 50 Han children with HSP, 66 healthy Mongolian and 96 healthy Han children as a control group. HLA-A and -B alleles were indentified by PCR-sequence-specific oligonucleotide analysis and were further analyzed by PCR-sequencing-based typing (SBT). Frequencies of HLA-A*11, HLA-B*15 in Mongolian patients and HLA-A*26, HLA-B*35, HLA-B*52 in Han patients were higher than those in the corresponding control group (P < 0.05), while frequencies of HLA-B*07 and -B*40 in Mongolian HSP patients were lower than those in the control group (P < 0.05). Further analysis using PCR-SBT showed that all HLA-A*11 were HLA-A*1101, and most HLA-B*15 were HLA-B*1501 in Mongolian HSP patients. All HLA-A*26 were HLA-A*2601 and HLA-B*35 were mostly HLA-B*3503 in Han patients. There were more Han patients with severe manifestations than Mongolian patients (P < 0.05). Frequencies of HLA-A*26, HLA-B*35 and HLA-B*52 in Han patients were higher than in Mongolian patients (P < 0.05). We conclude that HLA-A*11(*1101) and -B*15(*1501) are associated with susceptibility to HSP in Mongolian children and HLA-A*26(*2601), HLA-B*35(*3503) and HLA-B*52 are associated with susceptibility to HSP in Han children. HLA-B*07 and -B*40 may be protective genes in Mongolian children. The different frequencies of HLA-A and -B in Mongolian and Han children may be responsible for the different manifestations in these two ethnic groups.
Initial geometrical distribution and fluctuation can affect the collective expansion in relativistic heavy-ion collisions. This effect may be more evident in small system (such as B + B) than in ...large one (Pb + Pb). This work presents the collision system dependence of collective flows and discusses about effects on collective flows from initial fluctuations in a framework of a multiphase transport model. The results shed light on system scan on experimental efforts to small system physics.
•Fe3O4/rGO composites were easily prepared by a two-step method.•The mass ratio of Fe3O4 to rGO in the composites could be carefully controlled in the first step.•The content of Fe3O4 had great ...effect on the microstructure and capacitance of the composites.
Fe3O4/reduced graphene oxide (rGO) composites were prepared by a two-step method: solution precipitation followed by hydrogen reducing. The mass ratio of Fe3O4 to rGO in the composites could be carefully controlled in the first step. The structure and morphology of Fe3O4/rGO composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. The electrochemical properties of the composites as electrode of supercapacitors were investigated using cyclic voltammetry and galvanostatic charge–discharge tests. It was found that the mass ratio of Fe3O4 to rGO had great effects on the crystal size of Fe3O4, specific surface areas and pore volume, as well as the specific capacitance of the composites. The capacitance of the composite was higher than that of any individual component due to the synergetic effect between Fe3O4 and rGO. The composite exhibited an excellent cyclic stability and could maintain the initial capacity over 1000 cycles without any decay. This report provides useful clues in design and synthesis graphene-based composites for the applications as energy materials.
Initial geometrical distribution and fluctuation can affect the collective expansion in relativistic heavy-ion collisions. This effect may be more evident in small system (such as B + B) than in ...large one (Pb + Pb). This work presents the collision system dependence of collective flows and discusses about effects on collective flows from initial fluctuations in a framework of a multiphase transport model. The results shed light on system scan on experimental efforts to small system physics.
The development of a general use pavement joint sealant is described in this paper. A novel two-component polyurethane (PU) modified with hydroxyl terminated polydimethysiloxane joint sealant was ...developed for the needs of inland Chinese cement concrete pavement joint sealant production and applications. The performances of these sealants after hot pressing and hard drawing were also investigated. The cohesional strength of this new joint sealant material maintained 93·20% after hot pressing and hard drawing and was much higher than conventional PU and tar based PU joint sealants. This new sealant has superior tensile strength, cohesional strength, fatigue and aging resistance compared with currently used sealants.
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