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We experimentally design an integrated system composed of a conveyor belt and a posts array, which can simultaneously implement the function of size separation and transportation of disk particles. Differently sized particles through the post array exhibit two types of distinct migration modes that are responsible for the size separation. Furthermore, the dividing line between the two migration modes depends on the critical radius found in experiment. The relationship between the separation efficiency and the length of the post array and the packing fraction of particles is investigated quantitatively. Finally, a simplified model is proposed to predict a critical particle radius which is verified to be in accordance with experimental measurements. This research has a potential application prospect in some fields of industry.

The coupled Boussinesq equation (CBE) acts a key role in modeling the shallow water waves of two-layer fluid flow. However, it becomes powerless for the nonsmooth boundary. So, a fractal modification of the CBE is suggested in this paper. Aided by the semi-inverse method, we successfully construct its fractal generalized variational principle. In addition, three recent techniques, namely, the Sardar-subequation method, He’s frequency formulation method and subequation method, combined with the two-scale fractal dimension transform, are utilized to find abundant wave solutions. By these methods, various solutions expressed by the generalized hyperbolic functions, generalized trigonometric functions, hyperbolic functions and cosine function are obtained. With the aid of the mathematical software, the three-dimensional contours and two-dimensional curves are plotted to present the dynamic behaviors of the solutions. The results in this paper demonstrate that the proposed methods are powerful and effective to construct the traveling wave solutions of the fractal nonlinear evolution equations.

Hypoxic-ischemic (HI)-related brain injury, especially HI encephalopathy (HIE) is a leading cause of morbidity and disability in newborns. Long noncoding RNAs (lncRNAs) are implicated in the progress of HI brain damage. However, the mechanisms underlying the regulatory effects of lncRNA H19 on autophagy in HIE remain unknown. This study was designed to identify the potential mechanisms involving lncRNA H19 in HIE.We selected three HIE newborns and three healthy newborns for neonatal behavioral neurological assessment and screened the differentially expressed lncRNAs by microarray analysis and detected H19 expression in serum. After that, neonatal HIE rats were established and injected with H19 overexpression lentivirus vector or autophagy activator Rapa. The structure and apoptotic levels of brain tissue were observed, and righting reflex and geotaxis reflex were utilized to evaluate the short-term neurological function of HIE rats. The Morris water maze was performed to measure the long-term neurological functions of HIE rats. The binding relationships among H19/miR-19b/protein kinase B3 (Akt3) were verified. Levels of Akt3- and autophagy-related proteins were measured.H19 was upregulated in HIE newborns and rat models. The areas of cerebral infarction and apoptosis in neonatal HIE rats were increased, and the nerve functions were compromised. The overexpression of H19 alleviated nerve damage of neonatal HIE rats, and reduced autophagy of brain tissue. H19 upregulated Akt3 as a miR-29b sponge. The protective effects of overexpression of H19 on brain tissue and nerve functions of neonatal HIE rats were partially reversed by autophagy activator.H19 improved the brain tissue and alleviated nerve damage of neonatal HIE rats by upregulating the Akt3/mTOR pathway as a miR-29b sponge.· H19 overexpression reduces the nerve damage in neonatal HIE rats.. · H19 reduces autophagy in neonatal HIE rats by the miR-29b/Akt3/mTOR axis.. · Autophagy activator reverses the protection of H19 in neonatal HIE..

Horizontal flow of discrete objects through a bottleneck is prevalent and important in nature and industry. In this paper, we experimentally investigate the frictional effect of the bottom wall on the flow rate of granular particles passing through an aperture on a conveyor belt, since the bottom wall is always assumed to be trivial and the issue remains elusive. The flow rate monotonically increases with the coefficient of friction, finally approaching a saturation plateau. The bottom wall has an obvious effect on the flow rate. We show that the lateral motion of particles on both sides of the aperture, which is influenced by the coefficient of friction and can be converted into an effective aperture width, is responsible for the variation of the longitudinal flow rate. Our findings may provide a new way to manipulate the horizontal flow rate, particularly for the case where the aperture has to be fixed.

The stability and seismic behavior of geosynthetic-reinforced embankments during the earthquake is not well known. In this paper, the damage types of embankments were summarized, and the seismic stability of reinforced embankment were analyzed through an earthquake damage investigation in the Wenchuan earthquake region. Then, large-scale shaking table model tests were performed on the geosynthetic-reinforced embankment. The results show that the damage level of the reinforced embankment was almost less than that of the unreinforced embankment. The peak seismic earth pressure was nonlinear along the height of the embankment, the largest peak seismic earth pressure was roughly in the middle of the embankment slope. The peak ground accelerations (PGA) amplification factor first showed an increasing pattern and then a decreasing pattern with the increase of elevation, but there was a final increasing trend along the height of the reinforced embankment. The results can help to establish the proper design of the reinforcement embankments under earthquake conditions.

GC-SAW was used to carry out online sampling analysis of the main business sources, residential sources, and roads in Rizhao City from August 22 to 29 in 2020. The spatial distribution characteristics of various volatile organic compounds (VOCs) in the atmosphere were obtained, and the chemical reactivity of the main components was studied. The results showed that the VOCs with carbon atoms greater than 5 (VOC

To compare the clinical efficacy of femoral head replacement and internal fixation in the treatment of unstable intertrochanteric fractures in the elderly.Retrospective analysis of 70 cases of unstable intertrochanteric fractures treated from January 2016 to January 2019 and meeting the inclusion and exclusion criteria, 39 cases were fixed with closed reduction and new proximal femoral intramedullary nail(InterTAN), and 31 cases were treated with open trochanter reconstruction and artificial femoral head replacement. The operation time, intraoperative bleeding, hospital stay, weight bearing time, postoperative complication rate and hip function recovery (Harris score) were compared between two groups.All cases were followed up for 12 to 24 months. There were no significant differences in intraoperative bleeding and hospital stay between the two groups (InterTAN and femoral head replacement can treat unstable intertrochanteric fractures in the elderly, but femoral head replacement can move down early, improve the quality of life at the end of life, reduce postoperative complications and facilitate the treatment of coexisting diseases in internal medicine.

Acoustic wave collimation and enhancement are systematically investigated in the overlapped second and third bands of a two-dimensional square lattice sonic crystals by analyzing the band structure, equifrequency contour and field distribution. We find the collimation stems from a small negative-index of the second band, and an additional concave entrance can improve the collimation performance in the far field region. But for the third band, negative, zero, positive refraction and wave splitting may occur at the same time due to the simultaneous excitation of multiple Bloch modes, which ultimately destroy the collimation beam of the second band in the near field region. This work provides an insight into the collimation properties of the overlapped bands of sonic crystals with potential application in acoustic directional emission and wave manipulation.

In this paper, a novel and simple approach called the variational direct method (VDM) is applied to construct the exact traveling wave solutions of the system of ion sound and Langmuir waves (SEISLWs), which is under the influence of the ponderomotive force caused by a nonlinear force experienced by a charged particle in an inhomogeneous oscillating electromagnetic field due to high-frequency field. These exact solutions include the bright soliton, bright-like soliton, kinky-bright soliton, bright-dark soliton and periodic wave solutions, which are all presented through the numerical results in the form of 3-D plots. Obtained results show that the VDM is simple, straightforward and powerful, which is expected to open new perspectives for the traveling wave theory.

The Kundu-Mukherjee-Naskar equation can be used to address certain optical soliton dynamics in ( ) dimensions. In this paper, we aim to find its periodic wave solution by the Hamiltonian-based algorithm. Compared with the existing results, we found a good agreement, which strongly proves the correctness of the proposed method. Finally, the numerical results are presented in the form of 3-D and 2-D plots. The results in this work are expected to shed a bright light on the study of the periodic wave solution in physics.

Asparagus setaceus is an important ornamental plant and is important to study the sex chromosome evolution in genus Asparagus. Here the complete chloroplast (cp) genome sequence of A. setaceus was determined. The cpDNA is 156,978 bp in length, contains a large single copy region of 85,311 bp and a small single copy region of 18,641 bp, which was separated by a pair of inverted repeat regions of 26,513 bp each. The cp genome contains 132 genes, including 88 protein-coding genes, 6 ribosomal RNA genes, and 38 transfer RNA genes. Phylogenetic analysis indicates that A. setaceus is closely related to Asparagus officinalis and Asparagus schoberioides.

The discovery of topological edge states that unidirectionally propagate along the boundary of system without backscattering has enabled the development of new design principles for material or information transport. Here, we show that the topological edge flow supported by the chiral active fluid composed of spinners can even robustly transport an immersed intruder with the aid of the spinner-mediated depletion interaction between the intruder and boundary. Importantly, the effective interaction significantly depends on the dissipationless odd viscosity of the chiral active fluid, which originates from the spinning-induced breaking of time-reversal and parity symmetries, rendering the transport controllable. Our findings propose a novel avenue for robust cargo transport and could open a range of new possibilities throughout biological and microfluidic systems.

We experimentally present three methods for improving flow rate of disks driven through an aperture on a conveyor belt: modifying a flat bottom wall, tuning an initial packing configuration and the combination of both above, when the aperture and conveyor belt velocity cannot be altered. Improvements of up to 15.6% are reported. By measuring the packing density, vertical and horizontal velocity profiles in the flow of disks just before the aperture for various cases, we conclude that flow rate is mainly determined by the vertical velocity in each of these three methods. In addition, we qualitatively discuss that the horizontal velocity has two adverse effects on the vertical velocity. Potentially, this research can shed light on traffic flow or emergency evacuation of crowds.

This study investigated the influence factors on the seismic response and deformation modes of retaining walls using large-scale model shaking table tests. Experimental results showed that the distribution of peak seismic earth pressures along the height of a wall was a single peak value curve. The seismic earth pressures on a gravel soil retaining wall were larger than the pressures on the weathered granite and quartz retaining walls. Also, the peak seismic earth pressure increased with increases in the peak ground acceleration and the wall height. The measured seismic active earth pressures on a rock foundation retaining wall were larger than the calculated values, and the action position of resultant seismic pressure was higher than 0.33 H. In the soil foundation retaining wall, the measured seismic earth pressures were much smaller than the calculated values, while the action position was slightly higher than 0.33 H. The soil foundation retaining wall suffered base sliding and overturning under earthquake conditions, while overturning was the main failure mode for the rock foundation retaining walls.

The aim of this paper was to compare different effects of Tripterygium Glycosides Tablets from 6 different manufacturers on multiple organ injuries in rats and to explore mechanism of hepatotoxicity preliminarily from the perspective of apoptosis and oxidative stress. Rats were randomly divided into the groups normal, Zhejiang, Hunan, Hubei, Shanghai, Jiangsu and Fujian(7 groups with 16 rats in each group, sex in half). Rats were given Tripterygium Glycosides Tablets at 144 mg·kg~(-1)·d~(-1)(16 times the clinical equivalent dose) once a day according to its corresponding group like rats in Zhejiang group was given Tripterygium Glycosides Tablets from Zhejiang manufactures continuously for 20 days with the life and death situation of mice to be observed, then rats were executed to detect various indicators. RESULTS:: showed that 8 female rats in Zhejiang group died after 15 days of administration, the serum NEUT of rats in Hubei, Fujian and Shanghai groups was significantly lower than that of normal rats. The serum AST, ALT and/or TBiL levels were increased in all rats, and serum BUN and/or CRE levels of rats were also increased in Hunan, Hubei, Fujian and Shanghai groups. In dosage groups, testicular and ovarian coefficients of rats were reduced, the number of sperm were significant decreased while the rate of sperm malformation increased and sperm dynamics parameters of normal, especially in Jiangsu and Zhejiang groups. Liver histopathology and apoptosis of liver cells were observed in dosage groups, especially in Jiangsu and Hubei groups. In liver, Nrf2, HO-1 and Bcl-2 were inhibited and the protein expression level of Bax were increased simultaneously in dosage groups. These results showed that all Tripterygium Glycosides Tablets from 6 manufacturers could lead to chronic multiple organ injuries with disparate specialties in rats, and Jiangsu and Zhejiang groups were more toxic. It could be the mechanism promoting mitochondrial mediated Bax/Bcl-2 cell apoptosis signaling pathway and negatively regulating Nrf2/HO-1 oxidative stress signaling pathway that Tripterygium Glycosides Tablets from 6 different manufacturers resulted in chronic liver injury, the results above were for reference only in subsequent study.

Asparagus setaceusis a popular ornamental plant cultivated in tropical and subtropical regions globally. Here, we constructed a chromosome-scale reference genome ofA. setaceusto facilitate the investigation of its genome characteristics and evolution. Using a combination of Nanopore long reads, Illumina short reads, 10× Genomics linked reads, and Hi-C data, we generated a high-quality genome assembly ofA. setaceuscovering 710.15 Mb, accounting for 98.63% of the estimated genome size. A total of 96.85% of the sequences were anchored to ten superscaffolds corresponding to the ten chromosomes. The genome ofA. setaceuswas predicted to contain 28,410 genes, 25,649 (90.28%) of which were functionally annotated. A total of 65.59% of the genome was occupied by repetitive sequences, among which long terminal repeats were predominant (42.51% of the whole genome). Evolutionary analysis revealed an estimated divergence time ofA. setaceusfrom its close relativeA. officinalisof ~9.66 million years ago, andA. setaceusunderwent two rounds of whole-genome duplication. In addition, 762 specific gene families, 96 positively selected genes, and 76 resistance (R) genes were detected and functionally predicted inA. setaceus. These findings provide new knowledge about the characteristics and evolution of theA. setaceusgenome, and will facilitate comparative genetic and genomic research on the genusAsparagus.

Pb(Mn1/3Sb2/3)0.01(Ni1/3Nb2/3)0.495(Zr0.3Ti0.7)0.495O3+x wt% Ta2O5 (PMS–PNN–PZT, x = 0, 0.2, 0.4, 0.6, 0.8) lead piezoelectric ceramics were prepared by a traditional two-step solid-state reaction method. The effect of Ta2O5 content on the phase structure, microstructure, electrical properties and dielectric relaxation of PMS–PNN–PZT ceramics was investigated. The XRD patterns show that all ceramics have pure perovskite structure. Ta2O5 doping can promote the grain growth and improve electrical properties. And the ceramics have high relaxation behavior. When x = 0.4, it exhibits optimum electrical performance: d33 = 805 pC/N, kp = 66%, er = 6838, tanδ = 1.4%, Tc = 118.5 °C, γ = 1.9618, Ec = 3.652 kV/cm, Pr = 21.91 µC/cm2. This indicates that Ta2O5 can be used as an effective dopant in PMS–PNN–PZT ceramics and the ceramics can be used as the main material for multilayer ceramic capacitors and electro-strictive actuators.

(0.94 − x)K0.48Na0.52NbO3–0.06LiSbO3–xBiFeO3 (KNN–LS–xBF, x = 0, 0.1, 0.3, 0.5 and 0.7%) lead- free piezoelectric ceramics were prepared by a traditional two-step solid-state reaction method. The effect of BiFeO3 (BF) content on the phase structure, microstructure, electrical properties and dielectric relaxation of KNN–LS ceramics was investigated. The XRD patterns show that all ceramics have a pure perovskite structure. BiFeO3 doping can promote the grain growth and improve electrical properties. When x = 0.3% in KNN–LS–BF, it exhibits optimum electrical performance: d33 = 285 pC/N, kp = 54.3%, er = 2185, tanδ = 1.92%, Qm = 66, Tc = 340 °C, γ = 1.4732, Ec = 17.76 kV/cm, Pr = 21.48 µC/cm2. It is indicated that the ceramics have the potentialities to be used as the high temperature low frequency filters.

Heat treatment is an important mean to obtain excellent properties of all kinds of metal materials. The microstructure of 1045 steel modified with (NbTi)C nanoparticles was studied by means of optical, scanning electron, and transmission electron microscopy techniques. The effects of (NbTi)C nanoparticles in as-cast, normalized, as well as quenched and tempered (Q&T) steel were determined. The metallographic results showed that the normalized steel had a finer grain size than the as-cast steel. Tensile tests results showed that the strength and elongation of as-cast steel were significantly improved after heat treatment. Normalized steel showed a higher elongation and Q&T steel exhibited a higher strength. Under the same heat treatment condition, (NbTi)C nanoparticles modified 1045 steel showed a similar elongation with the base metal, whereas, the strength and hardness were evidently improved. The improved properties of the modified steel can be attributed to the refinement of the microstructure and uniform dispersion of (NbTi)C nanoparticles. Theoretical calculations of the strengthening contributions to different strengthening mechanisms indicated that particle strengthening plays a key role in strength improvement.

(NbTi)C nanoparticles were prepared using mechanical alloying (MA) and heat treatment process, and the nanoparticles pre-dispersed with Fe powder were introduced to 1045 steel. The microstructure of powders during different ball milling steps and as-casted steels were investigated using optical microscope (OM), scanning electron microscope (SEM), X-ray diffractometer (XRD) and transmission electron microscope (TEM). The results showed that the added carbides in as-cast steels were mainly composed of three kinds of types: uniform distribution; grain boundary center distribution and chainlike distribution. The uniformly distributed (NbTi)C nanoparticles in the matrix acted as effective heterogeneous nuclei that strongly refined the crystallization microstructure; the grain boundary center distributed particles interacted with the solid-liquid interface, thereby, hindered and restrained the movement of the solid-liquid interface; and the chainlike distributed nanoparticles move with the migration of solid-liquid interface and did not inhibit the interdendritic growth significantly. Compared with the cast steel without (NbTi)C nanoparticles, the modified steels have significantly refined microstructure, improved strength and increased hardness. With the further increase the amount of (NbTi)C nanoparticles, the efficacy of the (NbTi)C nanoparticles for refining crystallization microstructure weakened. Keywords: (NbTi)C nanoparticles, As-cast microstructure, Strength, Hardness, Refinement

Vertical integration for microelectronics possesses significant challenges due to its fast dissipation of heat generated in multiple device planes. This paper focuses on thermal management of a 3-D integrated circuit, and micro-channel cooling is adopted to deal with the 3-D integrated circuitthermal problems. In addition, thermal through-silicon vias are also used to improve the capacity of heat trans-mission. It is found that combination of microchannel cooling and thermal through-silicon vias can remarkably alleviate the hotspots. The results presented in this paper are expected to aid in the development of thermal design guidelines for 3-D integrated circuits.

Background In recent years, pyridylpyrazole derivatives, such as pyridylpyrazole-containing anthranilic diamide have attracted much attention by virtue of their useful insecticidal properties and unique action mode. Moreover, some pyridylpyrazole-containing compounds have also been found to possess significant fungicidal activities. With the aim of discovering new bioactive agrochemicals for crop protection, a series of poly-heterocyclic compounds containing pyridylpyrazole and aziridine, or β-lactam, or thiazolinone moieties were synthesized. Results A series of pyridylpyrazole-containing poly-heterocyclic compounds were obtained, and confirmed through IR, 1 H NMR, 13 C NMR, HRMS and elemental analysis. The crystalline structure of 4-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazol-5-yl)-3-chloro-1-mesitylazetidin-2-one (compound 13f) was determined to further illustrate a trans- configuration of the β-lactam motif. In addition, bioassays showed that most of these new compounds exhibited modest insecticidal activity towards Mythimna separate Walker at 200 µg mL-1 . Some of the compounds displayed excellent fungicidal activity towards some plant fungi, including Cercospora arachidicola (13j: EC50 = 14.5 µg mL-1 ), Physalospora piricola (12d and 13d: EC50 = 10.5 and 9.70 µg mL-1 ), Alternaria solani Sorauer (13j: EC50 = 7.29 µg mL-1 ), Puccinia sorghi Schw. (13d: control efficacy 99.0 ± 2.1% at 200 µg mL-1 ) and Erysiphe graminis (14d: control efficacy 95.0 ± 1.4% at 200 µg mL-1 ). Conclusion Compounds 12b-12e, 13a, 13d, 13f, 13j, 13 k and 14d could be considered potential fungicidal lead compounds to do further structural optimization. The structure-activity relationship analysis in this study brings some new understanding to the biological activities of N-pyridylpyrazole-containing compounds, and provides important information for the research and development of novel agricultural fungicides with poly-heterocyclic structures. © 2017 Society of Chemical Industry.

Electrocarboxylation of benzalacetone was studied experimentally and computationally. Only β-C carboxylate acid was obtained by potentiostatic electrolysis in the presence of CO2 under mild conditions. Density functional theory calculations revealed that benzalacetone dicarboxylation, both at the O and β-C positions rather than monocaboxylation at the β-C position, occurred during the process. Moreover, Mg2+ played a crucial role in the stabilization of intermediates, thereby promoting carboxylation.

Objective: Mental disorders of the elderly population in China deserve attention. Social health is significantly associated with depression. This study aimed to evaluate the rate of depressive symptoms and to test the relationships between social health and depressive symptoms among a large sample of community-dwelling elderly adults. Methods: We conducted a cross-sectional study among community-dwelling adults aged 60 years or above in Zhejiang Province, China. Face-to-face interviews were used to complete a structured questionnaire for all participants. We used the Social Health Scale for the Elderly (SHSE) to evaluate social health status and used the short form of the Geriatric Depression Scale to evaluate depressive symptoms. Multivariate logistic regression was used to evaluate the association between social health status and depressive symptoms. Results: Of the total of 3757 participants included, 1887 (50.23%) were female, and the mean±standard deviation (SD) age was (70.0±8.3) years. The rate of depressive symptoms was 25.92%. The social health score was higher in non-depressed participants than in depressed participants (raw score 50.7 vs. 48.3, P

Background The transfer of chloroplast DNA into nuclear genome is a common process in plants. These transfers form nuclear integrants of plastid DNAs (NUPTs), which are thought to be driving forces in genome evolution, including sex chromosome evolution. In this study, NUPTs in the genome of a dioecious plant Asparagus officinalis L. were systematically analyzed, in order to investigate the characteristics of NUPTs in the nuclear genome and the relationship between NUPTs and sex chromosome evolution in this species. Results A total of 3155 NUPT insertions were detected, and they represented approximated 0.06% of the nuclear genome. About 45% of the NUPTs were organized in clusters. These clusters were derived from various evolutionary events. The Y chromosome contained the highest number and largest proportion of NUPTs, suggesting more accumulation of NUPTs on sex chromosomes. NUPTs were distributed widely in all of the chromosomes, and some regions preferred these insertions. The highest density of NUPTs was found in a 47 kb region in the Y chromosome; more than 75% of this region was occupied by NUPTs. Further cytogenetic and sequence alignment analysis revealed that this region was likely the centromeric region of the sex chromosomes. On the other hand, the male-specific region of the Y chromosome (MSY) and the adjacent regions did not have NUPT insertions. Conclusions These results indicated that NUPTs were involved in shaping the genome of A. officinalis through complicated process. NUPTs may play important roles in the centromere shaping of the sex chromosomes of A. officinalis, but were not implicated in MSY formation. Electronic supplementary material The online version of this article (10.1186/s12870-019-1975-8) contains supplementary material, which is available to authorized users.

The well-known coupled Boussinesq–Burger equation can be used to describe the flow of the shallow water of the harbor. But when the boundary is nonsmooth, it becomes powerless. So, the fractal calculus is needed to be applied to it and the fractal coupled Boussinesq–Burger equation (FCBBe) is presented for the first time in this paper. By using the semiinverse method, we have successfully established the fractal variational formulation of the FCBBe, which can not only provide the conservation laws in an energy form in the fractal space but also reveal the possible solution structures of the equation. Then a novel variational approach based on He’s variational method and the two-scale transform are used to seek its periodic wave solutions. The main advantage of variational approach is that it can reduce the order of differential equation and make the equation more simple. Finally, the numerical results have been shown through graphs to discuss the effect of different fractal orders on the wave motion. The obtained results in this work are expected to shed a bright light on the study of fractal nonlinear partial differential equations in the fractal space.

The flowing behavior of granular materials is known as granular flow, which is ubiquitous in nature, industry and daily life. The behavior is not only related to flowing particles’ properties such as size, shape, density, and coarseness, but also to the external environments such as the flow channel and outlet. Therefore, the granular flow exhibits abundant non-linear phenomena. By now, great achievements have been made in the engineering field, but a unified theoretical framework is still absent. Consequently, it is very necessary to systemically investigate the effects of different parameters on the granular flow. This will be beneficial to deepen the understanding of flowing behavior, uncover the flowing mechanism, as well as potentially open a new avenue of establishment of the constitutive equations. This paper mainly focuses on the hopper flow including gravity-driven hopper, inclined hopper and velocity-driven horizontal hopper, and presents the dependence of the flow rate, flow pattern, particle velocity and packing fraction on various physical factors. These factors involve the outlet size, outlet position, outlet shape, coefficient of friction of inter-particles, particle shape, outlet number, external stimulus, obstacles, and hopper angle. The results can provide significant reference for tuning the flow rate and transportation efficiency, as well as serve as the basis for the future research.

The dynamical behavior of the column that made up binary granular beads is investigated systematically by tracking the displacement of particles in the collapse process. An experimental setup is first devised to control the quasi-static collapse of a granular column, and then observe the trajectories of tracer particles by using an industrial camera controlled by the image acquisition program. It is found that there exist two zones in column: a sliding region in which particles are moving in a layered structure; a static region within which particles are stationary. According to this analytical result, a dynamical model is developed to predict the trajectory evolution of particles in the space-time. The calculating result for the trajectories of particles on the selected layers is well consistent with the experimental observation.

Background N-Pyridylpyrazole derivatives have received continuous attention in agrochemical research during the last decade owing to their remarkable insecticidal or fungicidal potentials. To look for novel heterocyclic agrochemicals for increasing production of agriculture, a series of novel α-aminophosphonate derivatives containing N-pyridylpyrazole moiety were synthesized. Results The structures of the title compounds were confirmed via melting point, IR, 1 H NMR, 13 C NMR, 31 P NMR, HRMS and elemental analysis. The single crystal structure of diethyl (3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazol-5-yl)(2,6-dimethylphenylamino)methylphosphonate (compound 12b) was first reported. Moreover, the bioassays displayed that the title compounds exhibited modest or weak insecticidal activities against oriental armyworm at 200 μg mL-1 . The first investigation on the fungicidal potential of chlorantraniliprole showed no significant activities towards the six tested fungi found in this study, however, most of the title compounds displayed apparent in vitro fungicidal activity against some plant fungi, in particular excellent activities towards Physalospora piricola. Compounds 11a and 11b had EC50 values of 18.8 and 17.4 μg mL-1 , respectively, which were comparable with that of fungicide control triadimefon (EC50 = 24.7 μg mL-1 ) against Physalospora piricola. In addition, some compounds exhibited modest in vivo control efficacy at 0.5 mg mL-1 towards Sclerotinia sclerotiorum (11b: 30.1(±1.8)%), Rhizoctonia cerealis (11a: 20.4(±2.1)%; 11b: 30.2(±2.2)%), and Erysiphe graminis (11a: 30.3(±1.8)%; 12d: 40.2(±0.9)%). Conclusion Compounds 11a, 11b and 12d could be promising new lead structures for the development and discovery of novel fungicides towards Physalospora piricola and Erysiphe graminis. The structure-activity relationship (SAR) analysis provided useful guidance and new understanding for the design of novel pyridylpyrazole-containing agrochemicals. © 2019 Society of Chemical Industry.

We experimentally investigate the effect of the hopper angle on the flow rate of grains discharged from a two-dimensional horizontal hopper on a conveyor belt. The flow rate grows with the hopper angle, and finally reaches a plateau. The curve feature appears to be similar for different orifice widths and conveyor belt-driven velocities. On the basis of an empirical law of flow rate for a flat-bottom hopper, we propose a modified equation to describe the relation between the flow rate and hopper angle, which is in a good agreement with the experimental results.

Porcine circovirus type 2 (PCV2) is an important emerging pathogen that has been causatively associated with multifactorial disease syndromes in pigs and other species. It has a worldwide distribution and causes significant economic losses in the swine industry. Its genome is dynamically evolving through recombination and mutation, and the circulating genotypes of PCV2 strains in Asia are PCV2a, PCV2b and PCV2d. In this study, 12 PCV isolates were evaluated and identified by amplification, sequencing, and phylogenetic analysis, and the results revealed a new monophyletic group of PCV in China. More importantly, three of these isolates shared high homology within the ORF1 region with a strain of genotype PCV2c that was detected only in Denmark. Phylogeographic analysis of these isolates suggested that the isolates may have arisen in Denmark and that they were then transported to China.

Fatigue properties are important parameters for the safety design and security evaluation of gas transmission pipelines. In this work, the fatigue life at different stresses of full-thickness X80 pipeline steel plates with a ferrite/bainite dual-phase microstructure was investigated using a MTS servo-hydraulic universal testing machine; the fatigue crack propagation rate was examined with CT specimens by using an INSTRON 8874 testing machine. Results indicate that fatigue life increases as maximum stress decreases; as the maximum stress decreases to the maximum operating stress (440 MPa), the fatigue life is approximately 4.2×10 5 cycles. The fatigue crack of the full-thickness fatigue life specimens is generated at the surface of rolled steel plates and then the crack propagates and grows inward until a fracture is formed. During fatigue crack growth, a transitional turning point appears in the curve of da / dN with Δ K in the Paris region. The transitional turning point that divides the Paris region to two stages is approximately Δ K ≅30 MPa m 1/2 . The change in the growth rate ( da / dN ) is related to the variation of the crack path and in the fracture mode because of the possible microstructural sensitivity of fatigue crack propagation behavior. This study also discussed the effect of duple phase ferrite/bainite microstructure on fatigue crack initiation and propagation.

In this work, poly-thymine stabilized copper nanoclusters have been used as a fluorescence probe for melamine sensing for the first time. Melamine can bind to thymine through hydrogen bond, which could dramatically enhance the fluorescence intensity of poly-thymine stabilized copper nanoclusters. The enhancement factors (I-I0)/I0 increase linearly with the lgCmelamine over the melamine concentration range of 0.1 µM to 6 µM. The detection limit of melamine is 95 nM, which is 200 times lower than the US Food and Drug Administration estimate melamine safety limit 20 µM. Melamine in milk was detected with good recovery, which suggested that this novel fluorescence probe has great potential in practical application.

Contaminants released from sediment into rivers are one of the main problems to study in environmental hydrodynamics. For contaminants released into the overlying water under different hydrodynamic conditions, the mechanical mechanisms involved can be roughly divided into convective diffusion, molecular diffusion, and adsorption/desorption. Because of the obvious environmental influence of fine sediment ( 0.06 mm), non-cohesive fine sediment, and cohesive fine sediment are researched in this paper, and phosphorus is chosen for a typical adsorption of a contaminant. Through theoretical analysis of the contaminant release process, according to different hydraulic conditions, the contaminant release coupling mathematical model can be established by the N-S equation, the Darcy equation, the solute transport equation, and the adsorption/desorption equation. Then, the experiments are completed in an open water flume. The simulation results and experimental results show that convective diffusion dominates the contaminant release both in non-cohesive and cohesive fine sediment after their suspension, and that they contribute more than 90 % of the total release. Molecular diffusion and desorption have more of a contribution for contaminant release from unsuspended sediment. In unsuspension sediment, convective diffusion is about 10-50 times larger than molecular diffusion during the initial stages under high velocity; it is close to molecular diffusion in the later stages. Convective diffusion is about 6 times larger than molecular diffusion during the initial stages under low velocity, it is about a quarter of molecular diffusion in later stages, and has a similar level with desorption/adsorption. In unsuspended sediment, a seepage boundary layer exists below the water-sediment interface, and various release mechanisms in that layer mostly dominate the contaminant release process. In non-cohesive fine sediment, the depth of that layer increases linearly with shear stress. In cohesive fine sediment, the range seepage boundary is different from that in non-cohesive sediment, and that phenomenon is more obvious under a lower shear stress.

Porcine reproductive and respiratory syndrome (PRRS) is an economically important swine disease affecting swine worldwide. In this study, a total of 385 samples were collected from Shandong pig farms during 2013 and 2014, when pigs were not inoculated with any vaccine. Results indicated that, out of 385 samples, 47 (12.21%) were PRRSV-RNA-positive. The gene sequence analysis of 12 ORF5, 12 ORF7, and 8 Nsp2 of these samples was used to determine the molecular epidemiology of PRRSV in different parts of China’s Shandong Province. The phylogenetic tree based on these 3 genes indicated that the Chinese PRRSV strains could be divided into five subgroups and two large groups. The 8 study strains were clustered into subgroup IV, another 4 strains into subgroup I. The first 8 strains shared considerable homology with VR-2332 in ORF5 (96–97.5%), the other 4 strains shared considerable homology with JXA1 (94–98%). Phylogenetic tree of GP5 showed that the eight isolates formed a tightly novel clustered branch, subgroup V, which resembled but differed from isolate VR-2332. When examined using Nsp2 alone, the first 8 strains showed considerable homology with a U.S. vaccine strain, Ingelvac MLV (89.6–98.4%). One novel pattern of deletion was observed in Nsp2. The genetic diversity of genotype 2 PRRSV tended to vary in the field. The emergence of novel variants will probably be the next significant branch of PRRSV study.