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In this work, we investigate the quasi-two-body decays $B_c\to D^*h\to D\pi h$ with $h = (K^0,\pi^0,\eta,\eta^{\prime})$ using the perturbative QCD(PQCD) approach. The description of final state interactions between the $D\pi$ pair is achieved through the two-meson distribution amplitudes(DAs), which are normalized to the time-like form factor. The PQCD predictions on the branching ratios of the quasi-two-body decays $B_c\to D^*h\to D\pi h$ show an obvious hierarchy: $Br(B_{c}^+ \to D^{*+} K^{0}\to D^0\pi^+K^{0})=({5.22}_{-0.74}^{+0.86})\times{10}^{-6}, Br(B_{c}^+ \to D^{*+} \pi^{0}\to D^0\pi^+\pi^{0})=(0.93\pm0.26)\times{10}^{-7}, Br(B_{c}^+ \to D^{*+} \eta\to D^0\pi^+\eta) =({2.83}_{-0.52}^{+0.59})\times{10}^{-8}$ and $Br(B_{c}^+ \to D^{*+} \eta^\prime\to D^0\pi^+\eta^\prime)=({1.89}_{-0.36}^{+0.40})\times{10}^{-8}$. From the invariant mass $m_{D\pi}$-dependence of the decay spectrum for each channel, one can find that the branching fraction is concentrated in a narrow region around the $D^{*}$ pole mass. So one can obtain the branching ratios for the corresponding two-body decays $B_c\to D^{*+}h$ under the narrow width approximation. We find that the branching ratios of the decays $B_c\to D^{*+}h$ are consistent well with the previous PQCD calculations within errors. These predictions will be tested by the future experiments., Comment: 12 pages, 3 figures, accepted for publication in Chin. Phys. C

We probe the inner structure of the meson ${D}_{s0}^{*}(2317)$ through the decays of ${B}_{(s)}$ to two charmed mesons within the pQCD approach. Assuming ${D}_{s0}^{*}(2317)$ as a scalar meson with $\overline{c}s$ structure, we find that the predictions for the branching ratios of the decays ${B}^{+}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){\overline{D}}^{(*)0}$, ${B}^{0}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){D}^{(*)\ensuremath{-}}$ can explain data within errors. The branching ratios for the decays ${B}_{s}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){D}_{s}^{(*)+}$ are estimated to reach up to ${10}^{\ensuremath{-}3}$ order, which can be observed by the present LHCb and SuperKEKB experiments. In this work, the decay constant of the meson ${D}_{s0}^{*}(2317)$ is an input parameter. Unfortunately, its value has been studied by many references but with large uncertainties. Our calculation shows that a smaller decay constant of the meson ${D}_{s0}^{*}(2317)$ is supported by compared with the present data, say 55--70 MeV. We also calculate the ratios ${R}_{1}=\frac{\mathrm{Br}({B}^{+}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){\overline{D}}^{0})}{\mathrm{Br}({B}^{+}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){\overline{D}}^{*0})})$ and ${R}_{2}=\frac{\mathrm{Br}({B}^{0}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){D}^{\ensuremath{-}})}{\mathrm{Br}({B}^{0}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){D}^{*\ensuremath{-}})}$, which are valuable to determine the inner structure of ${D}_{s0}^{*}(2317)$ by compared with the experimental results. Our predictions for the ratios ${R}_{1,2}$ are consistent with the present data within errors. We expect that these two ratios can be well measured by the future experiments through improving the measurement accuracy for the decays ${B}^{+}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){\overline{D}}^{*0}$ and ${B}^{0}\ensuremath{\rightarrow}{D}_{s0}^{*+}(2317){D}^{*\ensuremath{-}}$.

We successfully employed bisphenol A and several different formyl-containing monomers as useful building blocks to construct a series of hydroxy-group-containing porous organic polymers in a sealed tube at high temperature. Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy are utilized to characterize the possible structure of the obtained polymers. The highest Brunauer–Emmet–Teller specific surface area of the phenolic-resin porous organic polymers (PPOPs) is estimated to be 920 m2 g–1. The PPOPs exhibit a highest carbon dioxide uptake (up to 15.0 wt % (273 K) and 8.8 wt % (298 K) at 1.0 bar), and possess moderate hydrogen storage capacities ranging from 1.28 to 1.04 wt % (77 K) at 1.0 bar. Moreover, the highest uptake of methane for the PPOPs is measured as 4.3 wt % (273 K) at 1.0 bar.

Four kinds of mannitol-based ketal-linked porous organic polymers ( MKPOPs ) were successfully synthesized through condensation reaction between aromatic acetyl monomers and mannitol, catalyzed by p -toluenesulfonic acid. The structure of resulting polymers was confirmed by Fourier transform infrared and solid-state 13 C nuclear magnetic resonance spectrum measurements. The porosities of MKPOPs were investigated by gas adsorption experiments and the results indicate high carbon dioxide uptake (up to 11.5 wt% at 273 K and 1.0 bar) for MKPOPs due to the predominant microporous and hydroxyl-rich structures. Remarkably, MKPOPs exhibit excellent selective adsorption performances for carbon dioxide over methane (9.9–14.2, IAST at 273 K and 1.0 bar). These studies are of significant importance for MKPOPs and their potential application in selective gas adsorption.

Triazine-based porous carbon materials (TPCs) have been synthesized via cyclotrimerization of aromatic tetranitriles and in situ carbonization. The resulting TPCs have high surface area (above 1200 m2 g−1), large pore volume (above 1.4 cm3 g−1), and hierarchical pore structures with micropores (0.63–1.24 nm) and mesopores (2.4–20 nm). Gas adsorption experiments demonstrate their promising hydrogen uptake capacity, up to 2.34 wt% at 77 K and 1.0 bar, due to the hierarchical porosity that facilitates the diffusion and adsorption of gas molecules.

We prepared a rigid triptycene derivative with three 2-ureido-4[1H]-pyrimidinone terminals, which was employed to construct a hydrogen-bonded organic polymer (HOP-1). The supramolecular organic polymer HOP-1 was permanently porous and exhibited outstanding sorption selectivity towards carbon dioxide over nitrogen (96 at 273 K).

An acid-resistant catalyst composed of nickel embedded in N-doped porous carbon is developed for the catalytic hydrogenation of nitrobenzene (NB) to p-aminophenol (PAP). The catalyst, due to a special electron donation from nickel to the N-doped porous carbon, shows an excellent catalytic performance and stability in sulphuric acid solution.

Three microporous spiro-centered poly(benzimidazole) networks were synthesized based on the condensation of di-/trialdehyde with 3,3,3′,3′-tetramethyl-1,1′-spirobisindane-5,5′,6,6′-tetrone in refluxing glacial acetic acid containing ammonium acetate. Fourier transform infrared and solid-state cross-polarization/magic-angle-spinning 13C NMR spectroscopy techniques were utilized to confirm the presence of a benzimidazole ring in the obtained polymers. The morphology can be observed from scanning electron microscopy and transmission electron microscopy images. The materials possess a Brunauer–Emmet–Teller specific surface area ranging from 520 to 600 m2 g−1. The highest hydrogen and carbon dioxide sorption capacity values of the obtained poly(benzimidazole) networks are up to 1.60 wt% (77 K and 1.0 bar) and 13.6 wt% (273 K and 1.0 bar), respectively, which are comparable to those of most of the microporous organic polymers.

Four acetal-linked porous organic polymers (MAPOP-1–4) have been synthesized by the reaction of multi-aldehyde monomers and mannitol under solvothermal conditions without a template or a metal catalyst. Fourier transform infrared and solid-state 13C cross-polarization/magic-angle-spinning nuclear magnetic resonance spectroscopic measurements were utilized to confirm the structures of the obtained polymers. MAPOPs exhibit high physicochemical stability and a considerable Brunauer–Emmett–Teller specific surface area ranging from 310 to 920 m2 g−1. Owing to their microporous structures, together with their hydroxyl-rich skeletons, MAPOP-1–4 show high carbon dioxide adsorption capability (11.6–13.5 wt% at 273 K and 1.0 bar), heat of adsorption (29.0–31.6 kJ mol−1), and remarkable CO2/CH4 selectivity (8.1–11.6, IAST at 273 K and 1.0 bar). These performances of MAPOP-1–4 make them promising materials in the applications of small gas storage and selective capture.

A series of benzimidazole-linked porous polymers are obtained by the condensation reaction between the o-aminobenzol end groups of building blocks (2,3,6,7,10,11-hexaaminotriphenylene, 3,3′-diaminobenzidine or 1,2,4,5-benzenetetraamine) and the aldehyde groups of building blocks [terephthalicaldehyde, 4,4′-biphenyldicarboxaldehyde, 1,3,5-tris(4-acetylphenyl)benzene or 1,3,5-tris(4-formylbiphenyl)amine] in one-pot synthesis without employing any catalyst or template. The existence of the imidazole ring in the obtained polymers could be identified by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The sphere-shaped morphology of the obtained polymers is observed through scanning electron microscopy. The polymers possess Brunauer-Emmett-Teller specific surface area values over 600 m2·g−1, showing hydrogen storage (up to 1.6 wt%, at 77 K and 1×105 Pa) and carbon dioxide capture (up to 12.6 wt%, at 273 K and 1×105 Pa) properties. Such polymers would possess good performance in the applications of gas storage and separation.

A series of microporous organic polymers with ketal linkages were synthesized based on the condensation of aromatic acetyl monomers with pentaerythritol. Fourier transform infrared and solid-state cross-polarization/magic-angle-spinning 13C NMR spectroscopy were utilized to confirm the ketal linkages of the resulting polymers. The morphology can be observed from scanning electron microscopy and transmission electron microscopy images. The materials possess Brunauer–Emmet–Teller specific surface area values ranging from 520 to 950 m2 g–1, and the highest hydrogen sorption capacity is up to 1.96 wt % (77 K and 1.0 bar), which is superior to that of most of microporous organic polymers. The facile and cost-effective preparation process and excellent gas sorption properties make these kinds of materials promising candidates for practical applications.

Carbazole-based oxidative coupling polymerization is an efficient method to prepare various porous polycarbazoles without requirement of any specific functional groups for coupling polymerization. Herein, facile preparation of porous conjugated polymers (CPOP-11 and CPOP-12) using porphyrin or Fe(II)–porphyrin as core structures through this approach is reported. The Brunauer–Emmett–Teller specific surface area of the obtained polymers is up to 1320 m2 g−1, which is comparable to metalloporphyrin based porous polymers prepared by other coupling polymerization methods. It is worth noting that the adsorption amount of toluene by CPOP-12 is high up to 1192 mg g−1 (about 13.0 mmol g−1) at its saturated vapor pressure, which would be very promising to eliminate harmful small aromatic molecules in the environment. As a kind of hydrophobic material, CPOP-11 could be more useful to extract methanol from water due to its high mass ratio of adsorbed methanol to water. Meanwhile, a porous polymer containing Fe(II)–porphyrin (CPOP-12) is also an effective catalyst for the formation of glycosyl sulfoxides from sulfides by promoting the transfer of oxygen atoms and can be reused without significant decrease in catalytic activity and amount of catalyst.

Facile preparation of microporous conjugated polycarbazoles via carbazole-based oxidative coupling polymerization is reported. The process to form the polymer network has cost-effective advantages such as using a cheap catalyst, mild reaction conditions, and requiring a single monomer. Because no other functional groups such as halo groups, boric acid, and alkyne are required for coupling polymerization, properties derived from monomers are likely to be fully retained and structures of final polymers are easier to characterize. A series of microporous conjugated polycarbazoles (CPOP-2-7) with permanent porosity are synthesized using versatile carbazolyl-bearing 2D and 3D conjugated core structures with non-planar rigid conformation as building units. The Brunauer-Emmett-Teller specific surface area values for these porous materials vary between 510 and 1430 m(2) g(-1) . The dominant pore sizes of the polymers based on the different building blocks are located between 0.59 and 0.66 nm. Gas (H2 and CO2 ) adsorption isotherms show that CPOP-7 exhibits the best uptake capacity for hydrogen (1.51 wt% at 1.0 bar and 77 K) and carbon dioxide (13.2 wt% at 1.0 bar and 273 K) among the obtained polymers. Furthermore, its high CH4 /N2 and CO2 /N2 adsorption selectivity gives polymer CPOP-7 potential application in gas separation.

As a novel class of porous materials, porous organic polymers possess high specific surface area and permanent pore structures. Researches focused on porous organic polymers have drawn great interests owing to their advantages in synthetic diversity, pore size controllability, and pore surface modifiability. The preparation of porous organic polymers has recently been developed rapidly because of their great potential applications in gas storage, separation, and heterogeneous catalysis. Herein, the research progresses in last two years in porous organic polymers in synthetic methods, properties and applications are introduced in this up-to-date review.

Considering the high reactivity of the C–H bonds in fluorobenzenes for direct arylation and special properties of fluorinated polymers, herein, synthesis of fluorinated porous organic polymers via direct C–H arylation polycondensation is explored. The obtained polymers (FPOP-1 and FPOP-2) are well characterized and show high porosities with Brunauer–Emmett–Teller specific surface area of above 1000 m2 g–1. Different pore size distribution (PSD) profiles of porous polymers can be obtained by selecting different core constructing monomers. FPOP-2 exhibits a relatively narrower PSD with the dominant pore size at about 0.63 nm, which is more suitable for adsorption of small gas molecules (H2, CO2, and CH4) than FPOP-1. As a porous fluorinated hydrophobic material, FPOP-2 possesses high adsorption ability for toluene (976 mg g–1 at saturated vapor pressure and room temperature) due to its high porosities and binding affinities between the guest molecules and the host network. The good sorption capacity of FPOP...

A series of microporous organic polymers with ketal linkages were synthesized based on the condensation of aromatic acetyl monomers with pentaerythritol. Fourier transform infrared and solid-state cross-polarization/magic-angle-spinning (13)C NMR spectroscopy were utilized to confirm the ketal linkages of the resulting polymers. The morphology can be observed from scanning electron microscopy and transmission electron microscopy images. The materials possess Brunauer-Emmet-Teller specific surface area values ranging from 520 to 950 m(2) g(-1), and the highest hydrogen sorption capacity is up to 1.96 wt % (77 K and 1.0 bar), which is superior to that of most of microporous organic polymers. The facile and cost-effective preparation process and excellent gas sorption properties make these kinds of materials promising candidates for practical applications.

Using the FLUENT software, this paper taking the current code for the design of building structures as the comparison standard, have numerical wind tunnel simulation of the wind the surface wind pressure on low layer double slope roof. It focuses on the analysis of the effects of turbulence model selection on the numerical simulation results, such as Spalart-Allmaras、Standard k −ε、RNG k −ε、Realizable k −ε、Standard k −ω、SST k −ω and RSM, to provide a basis for the reasonable selection of turbulence models.

At first, the paper introduces the international development trends of textiles, and indicates that we must conform to the ecological textile to resolve the green barriers. Then the paper introduces the concept and the essence of this ecological design, and raises the ways that achieves ecological textile from ecological evolving, ecological running, ecological designing, etc. At last, the paper introduces the ways of realizing ecological textile from four factors which are using regeneration material, reducing material consumption, elevating textile life and reusing the castoff textile.

Microporous organic polymers are a relatively new class of materials that show potential applications in various fields such as heterogeneous catalysis, adsorption, separation, and gas storage. The past decade has witnessed the development of microporous materials (i.e., materials containing pores of dimensions less than 2.0 nm) derived wholly from organic components. Several design strategies have emerged to produce organic polymers with permanent microporosity: i) hypercrosslinked polymers, where extensive crosslinking prevents close packing of polymeric chains, ii) polymers of intrinsic microporosity, where polymers are prepared from rigid, contorted structures that cannot pack efficiently, iii) conjugated microporous polymers, in which the inherent rigidity of most conjugated π-systems lends well to the generation of permanent microporosity, iv) covalent organic frameworks, which are crystalline materials formed by reversible condensation of appropriate multifunctional building blocks. On the basis of recent research progress, this paper will introduce the polymers of intrinsic microporosity and conjugated microporous polymers in major, and the other two kinds of polymers are also involved briefly.

We demonstrated the synthesis of five kinds of microporous organic polymers based on aldol self-condensation of di- and multiacetyl-containing building blocks catalyzed by thionyl chloride. The α,β...

Novel glucosamine hydrochloride functionalized water-soluble conjugated polyfluorene was easily synthesized through Cu(I)-catalyzed azide/alkyne "click" ligation and Suzuki coupling polymerization. The water-solubility and biocompatibility of the polymer were improved after grafting glucosamine hydrochloride to the side chains of the conjugated polymer. As a fluorescent model system of chitosan, its interaction with single-stranded DNA was studied by spectro-fluorometric titration.

Cyclodextrins (CDs) show functionality, biocompatibility, and host-guest inclusion capacity with a variety of molecules. These unique properties offer great potential for the exploitation of CDs as drug delivery systems. An easy, green, and effective synthetic approach was described to develop CD-based porous nanospheres (CDPNSs) with a size distribution from 100 to 400 nm. A new cross-linker tris(2-aminoethyl)amine was used to cross-link modified β-CD at room temperature. The resulting CD-based polymers (CDPs) were reshaped from a random morphology into a spherical shape during a dialysis process, and CDPNSs were obtained. The morphologies of CDPs and CDPNSs were observed with scanning electron microscopy. The average diameter and the size distribution of CDPNSs were determined by dynamic light scattering. The structures of the resulting products were characterized by using Fourier transform infrared spectroscopy, 1H NMR spectroscopy, solid-state 13C CP/MAS NMR spectroscopy, and X-ray diffraction. Furthermore, a study was conducted on drug loading and in vitro release behavior of CDPNSs, which was monitored by ultraviolet spectroscopy. The prepared CDPNSs show the potential as drug delivery systems.

Smoking is the primary cause of lung cancer and is linked to 85% of lung cancer cases. However, how lung cancer develops in patients with smoking history remains unclear. Systems approaches that combine human protein-protein interaction (PPI) networks and gene expression data are superior to traditional methods. We performed these systems to determine the role that smoking plays in lung cancer development and used the support vector machine (SVM) model to predict PPIs. By defining expression variance (EV), we found 520 dynamic proteins (EV>0.4) using data from the Human Protein Reference Database and Gene Expression Omnibus Database, and built 7 dynamic PPI subnetworks of lung cancer in patients with smoking history. We also determined the primary functions of each subnetwork: signal transduction, apoptosis, and cell migration and adhesion for subnetwork A; cell-sustained angiogenesis for subnetwork B; apoptosis for subnetwork C; and, finally, signal transduction and cell replication and proliferation for subnetworks D–G. The probability distribution of the degree of dynamic protein and static protein differed, clearly showing that the dynamic proteins were not the core proteins which widely connected with their neighbor proteins. There were high correlations among the dynamic proteins, suggesting that the dynamic proteins tend to form specific dynamic modules. We also found that the dynamic proteins were only correlated with the expression of selected proteins but not all neighbor proteins when cancer occurred.

With the view of emergency system optimization, this paper considers the resource requirements, emergency rescue time of emergency demand points in emergency response systems and total system cost, set up a model for a emergency response system base on a partial differential equation, and it can be solved by iteration algorithm with central difference scheme. Numerical examples show that the proposed model and algorithm can solve the target location problem for optimizing the emergency response system.

This paper approached a cover algorithm for location problem in the optimization of emergency system. With the considering of requirements, emergency response time and total system cost, a distribution of the dispatch points can be obtained by the algorithm. The demands region/points can be covered by the circles with radius d and everyone takes a dispatch point as center. Contributes to the well property of Gaussian convolution, the local demands level can be obtained and the distribution based on covers and sorted demands is more efficient. Numerical examples show that the proposed algorithm can solve the location problem in the optimization of emergency systems.

Novel glucosamine hydrochloride functionalized water-soluble conjugated polyfluorene was easily synthesized through Cu(I)-catalyzed azide/alkyne "click" ligation and Suzuki coupling polymerization. The water-solubility and biocompatibility of the polymer were improved after grafting glucosamine hydrochloride to the side chains of the conjugated polymer. As a fluorescent model system of chitosan, its interaction with single-stranded DNA was studied by spectrofluorometric titration.

A triazine-based porous carbon material (TPC-1) was prepared directly from a fluorinated aromatic nitrile in molten zinc chloride. Trimerization of the nitrile and subsequent defluorination carbonization of the polymeric network result in the formation of TPC-1. The defluorination process is reversible and can etch the polymeric network to release CFn, thereby generating additional porosity and rendering TPC-1 a nitrogen-rich porous material. TPC-1 shows a high BET surface area of 1940 m2 g−1 and contains both micropores and mesopores, which facilitate the diffusion and adsorption of gas molecules. Gas adsorption experiments demonstrate outstanding uptake capacities of TPC-1 for CO2 (4.9 mmol g−1, 273 K and 1.0 bar), CH4 (3.9 mmol g−1, 273 K and 1.0 bar), and H2 (10.1 mmol g−1, 77 K and 1.0 bar). This straightforward synthesis procedure provides an alternative pathway to prepare high-performance porous carbon materials.

A series of cyclodextrin-based microporous carbon materials were synthesized through a facile one-step solvothermal carbonization process. The results of Fourier transform infrared and solid-state 13C CP/MAS nuclear magnetic resonance studies show that the obtained carbon materials contain a large amount of oxygen-containing functional groups, such as hydroxyl, carbonyl, and carboxyl groups. Spheres can be observed in the scanning electron microscopy and high resolution transmission electron microscopy images. These kinds of carbon materials possess Brunauer–Emmet–Teller specific surface area data ranging from 600 to 700 m2 g−1, which are much higher values than those of carbon materials obtained from hydrothermal carbonization processes. Furthermore, these materials show moderate sorption capabilities for hydrogen (up to 1.07 wt%, 77 K and 1.0 bar) and carbon dioxide (up to 12.7 wt%, 273 K and 1.0 bar). The excellent characteristic of these materials make them promising candidates for gas storage.

We demonstrate the synthesis of two triptycene-based microporous poly(benzimidazole) networks through condensation of triptycene-hexone with dialdehyde in refluxing glacial acetic acid containing ammonium acetate. The benzimidazole-linkage in the resulting polymers is confirmed by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The spindle-shaped morphology of the obtained polymers was also observed through scanning electron microscopy. The materials, with Brunauer–Emmet–Teller (BET) specific surface area over 600 m2 g−1, possess a good hydrogen storage capacity (up to 1.57 wt% at 77 K and 1.0 bar) and a high carbon dioxide uptake (up to 14.0 wt% at 273 K and 1.0 bar). These excellent performances would probably make them promising candidates for gas-selective adsorption, heterogeneous catalysis, and proton-exchange membrane fuel cells.

Graphene-Mn3O4 (GMNO) hybrid porous material is prepared by a hydrothermal method and its performance in carbon dioxide adsorption is investigated. In the synthesis of the GMNO materials, MnO(OH)2 colloid obtained by the hydrolysis of Mn2+ in basic solution was using as the precursor of the Mn3O4. After a hydrothermal reaction of the mixture of graphene oxide (GO) and MnO(OH)2, GO was reduced into graphene and the MnO(OH)2 was transformed into Mn3O4 with enhanced crystallization. X-ray diffraction, thermal gravimetric analysis, transmission electron microscopy, infrared spectra and Raman spectroscopy were taken to characterize the hybrid material. The porosity and the carbon dioxide adsorption ability are measured by gas sorption analysis, in which the as-prepared GMNO hybrid materials exhibit a specific surface area ranging from 140 to 680 m2 g−1 and a maximum carbon dioxide capacity of about 11 wt%.