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A graph is said to be symmetric if its automorphism group is transitive on its arcs. This article is one of a series of articles devoted to characterizing prime-valent arc-transitive graphs of square-free order or twice square-free order. In this article, we determine all 7-valent symmetric graphs of order 2pq and 11-valent symmetric graphs of order 4pq.

In this note we point out an error in a recent paper on flag-transitive block designs with gcd $$(r,\lambda )=1$$ , and we prove a result correcting the error.

A novel polysaccharide was extracted from Coriandrum sativum L. at a yield of 4.56 ± 0.17% (n = 3). The extraction was optimized using response surface methodology: powder-to-liquid ratio 1:21 g/ml, extraction time 188 min, temperature 81°C, and three replicate extractions. The purified polysaccharide had an average molecular weight of 1.30 × 10

Phosvitin has excellent calcium binding capacity, related to its phosphopeptides. The phosphopeptides may be used as functional ingredients for improving calcium bioavailability, but the calcium-binding mechanism is unclear. In this study, a novel phosvitin phosphorylated pentapeptide (Glu-Asp-Asp-pSer-pSer, EDDpSpS) was selected to prepare an EDDpSpS calcium complex (EDDpSpS-Ca), and the calcium-binding mechanism and bioavailability investigated. The calcium-binding capacity of EDDpSpS was up to 468 ± 152.80 mg/g. Calcium ions prompted the folding of the EDDpSpS structure to form spherical nanoparticles. The calcium binding sites of EDDpSpS involved peptide bonds, carboxyl, amino, and phosphate groups. Molecular forces involved in these interactions were electrostatic in nature. Moreover, EDDpSpS-Ca had excellent bioavailability when compared to CaCO

Sludge-based activated carbon (ZAC) was successfully employed as both adsorbent and catalyst for the oxidation process of reactive yellow 86 (RY86) and reactive black 5 (RB5). Physicochemical prope...

This paper is a contribution to the classification of flag-transitive 2- $$(v,4,\lambda )$$ designs. We determine all such designs admitting $$G=PSL(2,q)$$ as a flag-transitive automorphism group.

Consumer behaviors have always been the hot spot of the study. With the arrival of the network age and the popularity of e-commerce, the consumption pattern of shopping online is beginning. Until December of 2014, there were 649 million Internet users in China, and it's increasing. In the year of 2014, the number of most mainstream online shoppers has increased by 23.7% and shopping online has become an irresistible trend. New consumption mode can produce a new research subject, the study of Internet consumer behaviors becomes very important. This article used LocoySpider, a data mining software, to mine Taobao online reviews. Through the analysis of online reviews, we can study the effect of online reviews on consumer behaviors. During the study, we set the risk perception as intermediary variable. By the study, we can help the electronic commercial enterprises to attract customers, retain customers and reduce the information search cost.

The paper reports on an investigation of structure of block-transitive automorphism groups of a triple system. We prove that if G is a block-transitive automorphism group of a triple system T , then G cannot be of simple diagonal or twisted wreath product type. Furthermore, if G is of product type, then Soc ( G ) = A 5 × A 5 and T is the unique T S ( 25 , 12 ) .

Simetrični grafi valenc 3, 4 in 5, katerih red je prost kvadratov, so bili klasificirani v literaturi. V tem članku predstavimo popolno klasifikacijo simetričnih grafov, katerih red je prost kvadratov, in imajo poljubno praštevilsko valenco, ki dopušča rešljivo ločno-tranzitivno grupo, ter popolno klasifikacijo 7-valentnih simetričnih grafov, katerih red je prost kvadratov.

A graph is called symmetric if its automorphism group is transitive on its arcs. In this paper, we classify symmetric graphs of order four times an odd square-free integer and valency seven. It is shown that, either the graph is isomorphic to one of 9 specific graphs or its full automorphism group is isomorphic to PSL ( 2 , p ) , PGL ( 2 , p ) , PSL ( 2 , p ) × Z 2 or PGL ( 2 , p ) × Z 2 with p ≡ ± 1 ( mod 7 ) a prime.

Arc-transitive cyclic covers of symmetric graphs with a specific prime valency and order twice a prime have been studied by nearly ten papers in the literature. In this paper, we will give a general characterization of arc-transitive cyclic covers of graphs with any prime valency and order twice a prime.

Sludge-based activated carbon (ZAC) was successfully employed as both adsorbent and catalyst for the oxidation process of reactive yellow 86 (RY86) and reactive black 5 (RB5). Physicochemical properties of the prepared sewage sludge-derived activated carbon were evaluated by N

Hua et al. (Discrete Math 311, 2259---2267, 2011) and Yang et al. (Discrete Math. 339, 522---532, 2016) classify arc-transitive pentavalent graphs of order 2pq and of order 2pqr (with p, q, r distinct odd primes), respectively. In this paper, we extend their results by giving a classification of arc-transitive pentavalent graphs of any square-free order.

Li et al. [‘On finite self-complementary metacirculants’, J. Algebraic Combin.40 (2014), 1135–1144] proved that the automorphism group of a self-complementary metacirculant is either soluble or has $\text{A}_{5}$ as the only insoluble composition factor, and gave a construction of such graphs with insoluble automorphism groups (which are the first examples of self-complementary graphs with this property). In this paper, we will prove that each simple group is a subgroup (so is a section) of the automorphism groups of infinitely many self-complementary vertex-transitive graphs. The proof involves a construction of such graphs. We will also determine all simple sections of the automorphism groups of self-complementary vertex-transitive graphs of $4$-power-free order.

The paper presents classifications of edge-transitive cyclic regular covers of the complete graphs K 5 and K 6 , and arc-transitive cyclic regular covers of the complete graph K 7 . Two new infinite families of transitive graphs of valency 4 and 6 are found. As an application, tetravalent edge-transitive graphs of order 5 p 2 with p a prime are classified.

A graph is called arc-regular if its full automorphism group acts regularly on its arc set. We characterise arc-regular graphs with prime valency of cube-free order, and prove that such graphs of order twice an odd cube-free integer are normal Cayley graphs or binormal Cayley graphs, and there is no such graph of order four times an odd cube-free integer, which generalises certain previous results in the literature; we also classify arc- regular graphs with prime valency of order eight times an odd square-free integer, and found some new arc-regular graphs. Moreover, motivated by the obtained results, a conjecture and some problems are proposed.

The 18th Central Committee of the Communist Party of China (CPC) convened its fifth plenary session in Beijing, which put forward that we have to firmly establish and effectively implement five development concepts, innovation, coordination, green, open and shared. It means that the concept of green plays an important role for the economy. The industrial transfer and industrial undertaking are the important means to realise the coordinated development for the Jing-Jin-Ji region. So, we studied the industrial undertaking for Hebei province considering the environment. Firstly, define 'the comparison of environmental input-output rates' to improve the industrial gradient coefficient. Secondly, make short-term choice to undertake industries in Hebei province. Thirdly, use the 'co-integration' and 'impulse response' to make the long-term selection. Finally, seven industries, such as textile and garment, catering accommodation production, education and so on, are the key to undertake industry in Hebei province.

Pore water extract samples derived from six peat types differing in depositional environment were characterized using pyrolysis GC/FID/FT-IR, pyrolysis GC/MS, and FT-IR spectroscopy. Pyrolysis GC/FID/FT-IR analysis revealed many by-products resulting from the thermal degradation of the major constituents of plant material: cellulose and lignin. Comparison of the pyrolysis chromatograms showed large variations in the chemical compositions of the pyrolysis products from sample to sample. Results of the FT-IR analysis revealed major differences around 100 cm −1 (CO stretch region) and betwenn 1500 and 1800 cm −1 (CC and CC stretch region). These two regions have previously been identified as representing cellulose and lignin, respectively. The six different extracts are compared based on their resulting FT-IR spectra and pyrolysis chromatograms. Similarities and differences are emphasized along with any conclusions drawn based on these studies.