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A main challenge in design with long discontinuous fibre-based sheet moulding compound (SMC) is to understand flow-induced fibre orientation in the part. There are very few experimental methods for characterising the fibre orientation distribution in carbon fibre SMC. Consequently, even though process simulation models for predicting fibre orientation have been developed, the confidence in using these models remains low. This research aims to study the fibre orientation distribution in compression moulded carbon fibre SMC using a combined experimental and numerical approach. A recently developed micro-CT scanning-based method will be adopted to study carbon fibre SMC samples of various sizes. The data collected from the experimental study will be used to assess the predictive validity of selected commercial process simulation packages.

ABSTRACTStrip tension fluctuation caused by the attenuation of a furnace roller’s surface roughness leads to strip deviation in continuous annealing. After several field experiments and theoretical studies, this work established a model for the surface roughness attenuation of a furnace roller during continuous annealing. The model is fully integrated with the equipment and process features of a continuous annealing unit. With the stability of strip travelling as the control object and the absence of strip deviation and buckling as constraints, a tension compensation technique of continuous annealing was developed, and a related theory was applied to production and practise. Software was also developed for predicting the roughness attenuation of a furnace roller during continuous annealing and determining tension compensation for a specific process of the unit. Integrated optimisation of tension parameters in all processes of continuous annealing was also achieved.

Several problems, such as strip deviation and buckling, are encountered in the continuous annealing process. In this study, equipment and process features of continuous annealing, as well as the advantages and disadvantages of single taper roller and double taper roller in the prevention and treatment of the buckling and strip deviation were considered. Basing on a number of field experiments and theoretical studies, a new set of furnace roller profile curve was proposed and a set of optimisation model suitable for furnace roller was established, with travelling stability of the strip as the objective function. Test results of field production showed that the strip exhibited high speed and stability after optimisation, and the service cycle of the furnace roller was considerably improved. The results of this study provide an important economic benefit for the site and are valuable for further popularisation and application.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative option for treatment of some malignant and non-malignant hematological diseases. However, post-HSCT patients are severely immunocompromised and susceptible to viral infections, which are a major cause of morbidity and mortality. Although antiviral agents are now available for most types of viral infections, they are not devoid of side effects and their efficacy is limited when there is no concomitant antiviral immune reconstitution. In recent decades, adoptive transfer of viral-specific T cells (VSTs) became an alternative treatment for viral infection after HSCT. However, two major issues are concerned in VST transfer: the risk of GVHDand antiviral efficacy. We report an exhaustive review of the published studies that focus on prophylactic and/or curative therapy by donor VST transfer for post-HSCT common viral infections. A low incidence of GVHD and a good antiviral efficacy was observed after adoptive transfer of VSTs from HSCT donor. Viral-specific T-cell transfer is a promising approach for a broad clinical application. Nevertheless, a randomized controlled study in a large cohort of patients comparing antiviral treatment alone to antiviral treatment combined with VSTs is still needed to demonstrate efficacy and safety.

This paper considers the equipment and technological characteristics of continuous annealing process (CAP) to solve the issue of strip buckling. It analyses the mechanism of hot buckling and transverse compressive stresses from internal and external forces. A basic description of strip buckling is given together with a new concept of a buckling index. The critical buckling condition is presented, and the model of strip buckling index in the CAP is proposed. The distribution of strip buckling index in different sections of the process is analysed quantitatively along with the influence of incoming strip shape, transverse temperature difference, roller profile, friction coefficient, set tension and strip processing speed on the strip hot buckling index in CAP. Results show that with the influence of thermal stress, the transverse compressive stress that affects the middle part of the strip is largest in the heating section, which is also where hot buckling occurs most easily; centripetal force is dominant in the soaking and slow cooling sections, and in these sections buckling occurs at the roller shoulder. In different sections, the strip buckling index distribution differs, whereas the influence of other parameters on buckling index remains similar.

Cone defect in rolls may be caused by bad grinding. Cone defect leads to shape defect in unilateral waves of the finished strip. By using a six-high mill as example and by considering the features of the devices and technology, an influence model of roll with cone defect and a suitable shape control technology of a six-high mill was established to guarantee good shape. This model was then applied to a production practice of 1220 cold continuous rolling units. Quantitative analysis of different kinds of roll with cone defect and its effect on shape control shows that the additional shape caused by cone defect are unilateral waves. In conclusion, optimising the amount of tilt settings can effectively control the additional shape caused by cone defect, which provides enterprises with a useful reference for the high-precision control of shape.

A simple mechanical model is proposed to describe the dynamics system of the taut inclined cable excited by the deck vibration. Using Galerkin method, the dynamics system is simplified into a one-degree of freedom nonlinear system. Average method is used to obtain the average equations and bifurcation equation. Bifurcation maps are obtained and used to reveal the evolution mechanism of period-1 motion to period-2 motion. Several motion forms are discussed and evolution progress between different motions is studied. Several kinds of parametric resonance are revealed in various parameter regions. The conclusions indicate that the parametric resonance excited by the frequency ratio 3:2 is significant should be paid more attention.

This work is concerned with the extrusion blow molding of polymeric blends containing thermotropic liquid crystalline polymer (TLCP) and high density polyethylene (HDPE), using a single screw extruder. The TLCP is synthesized from terephthalic acid, 4-hydroxybenzoic acid, hydroquinone and hydroquinone derivatives, the melting point of which is 280 °C. Because the TLCP is usually processed at much higher temperatures than HDPE, the thermal stability of HDPE at elevated temperature is evaluated. It is shown that HDPE is relatively stable in the processing temperature range of the TLCP used in this work (260 to 300 °C). Bottles are successfully produced from the blends containing 10, 20 and 50 wt% TLCP. The TLCP/HDPE blend bottles exhibit enhanced modulus relative to pure HDPE. However, the improvement in tensile strength is marginal. At 10 and 20 wt% TLCP contents, the TLCP phase exists as platelets aligning along the machine direction, while a co-continuous morphology is observed for the blend containing 50 wt% TLCP. To further enhance the mechanical properties of the blends, the preliminary effectiveness of maleic anhydride grafted HDPE (MA-g-HDPE) as a compatibilizer is studied. The injection molded ternary blends of TLCP/HDPE/MA-g-HDPE have demonstrated superior mechanical properties over the binary TLCP/HDPE blends, which suggests MA-g-HDPE as a potential compatibilizer for developing high performance TLCP/HDPE containers with enhanced mechanical properties.

ABSTRACTSapium sebiferumseeds from Huangshan, Wuhan, and Guiyang in China were studied to identify differences in their 1,000-seed mass and in concentrations of inhibitors of germination in the seed coat or endosperm extracted using methanol or acetone. Seed mass varied significantly in relation to origin, with the highest mass observed in seeds from Wuhan, followed by seeds from Huangshan and Guiyang. Extracts of seed coats or endosperm caused a marked inhibition of the germination index of cabbage seeds, but less inhibition of germination percentages. Endosperm extracts had a stronger inhibitory effect on cabbage seed germination than seed coat extracts. Inhibitor concentrations in whole seeds also varied with seed origin. Seeds from Wuhan exhibited a significantly higher level of inhibition than those from Guiyang or Huangshan, but no significant differences were observed between seeds from Guiyang and Huangshan. The efficacy of methanol or acetone extraction was also evaluated. For whole seeds from Huangshan and Guiyang, methanol was more effective than acetone, while acetone performed better than methanol for seeds from Wuhan.

Our previous study reported that Epstein–Barr virus(EBV)-encoded latent membrane protein 1 (LMP1) could induce development of CD44+/Highstem-like cells in nasopharyngeal carcinoma (NPC). However, the molecular mechanisms that underlie modulation of cancer stem cells (CSCs) in NPC remain unclear. Here, we show that LMP1 induced CSC-like properties through promotion of the expression of epithelial–mesenchymal transition-like cellular markers and through alterations in differentiation markers. Furthermore, LMP1 activated and triggered phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, which subsequently stimulated expression of CSC markers, development of side population and tumor sphere formation. This suggests that PI3K/AKT pathway has an important role in the induction and maintenance of CSC properties in NPC. Similarly, PI3K/AKT pathway was also activated by phosphorylase in LMP1-induced CD44+/Highcells. In addition, LMP1 greatly increased expression of miR-21 and downregulated expression of the miR-21 target, PTEN. Overexpression of miR-21 by transfection of miR-21 mimics into LMP1-transformed cells led to phosphorylase-mediated activation of the PI3K/AKT pathway and induction of CSCs. On the contrary, phosphorylation of the PI3K/AKT pathway and the expression of CSC were reversed by an miR-21 inhibitor. The specific inhibitor (Ly294002) of PI3K/AKT pathway significantly decreased expression of miR-21 and CSC markers and upregulated the expression of PTEN, which indicates that miR-21 and PTEN are the downstream effectors of PI3K/AKT and that expression of these two effectors are related to the development of NPC CSCs. Taken together, our novel findings indicate that LMP1, PI3K/AKT, miR-21 and PTEN constitute a positive feedback loop and have a key role in LMP1-induced CSCs in NPC.

The conventional universal crown mill (UCM) temper mill cannot be controlled well for asymmetric high-order complex wave shapes; thus, a novel type of asymmetric universal crown temper mill (AS-UCM) was designed, which was configured for asymmetric bending of the work roll and intermediate roll, as well as asymmetric axial shifting of the intermediate roll. The corresponding shape control technology was established. Taking the typical production process as an example, the present study quantitatively analysed the control effect of AS-UCM and the ordinary UCM temper mill on asymmetric high-order complex wave shapes. Moreover, the related technology was commercially applied to the 750 mm AS-UCM with great economic benefits.

We propose the perfect all-carbon axisymmetric spintronic devices consisting of a zigzag-edged trigonal graphene (ZTG) linked to left and right zigzag-edged graphene nanoribbons (ZGNR) electrodes via carbon atomic chains (CACs). To ensure the stability of the system, the edge carbon atoms are passivated by hydrogen atoms. The self-consistent density functional theory (DFT) calculations show that the simple all-carbon system possesses the prefect spin-filtering property at a wide voltage region from −1.0 to 1.0 V. More importantly, the proposed system can act as a perfect dual spin diode in the antiparallel (AP) spin configuration, and the single-spin rectifying ratio can reach 103. When we add the number of the CACs linked to the left ZGNR electrode, the device shows the obvious single-spin negative differential resistance (NDR) behavior, which originates from the appearance of the localized states in the region of the left ZGNR electrode and ZTG. Meanwhile, the perfect spin-filtering and dual spin-diode properties are also retained in the all-carbon spintronic device, and the single-spin rectifying ratio can be enhanced to about 104.

Abstract: Regenerative medicine represents a promising perspective on therapeutic angiogenesis in patients with cardiovascular disease, including heart failure. However, previous or ongoing clinical trials show ambiguous outcomes with respect to the benefit of regenerative therapy by means of bone marrow stem cell infusion in myocardial infarction patients. Therefore, it is necessary to set up a rational therapeutic strategy in the treatment of congestive heart failure. Chemokines, cytokines and growth factors, as well as pharmaceutical agents, may have an impact on endothelial progenitor cell (EPC) physiology and thus can provide targets for pharmacological intervention. Indeed, EPCs and stem cell niches both in bone marrow and myocardial tissue can be treated as an integral target for recruitment of EPCs from the bone marrow to the cardiac ischaemic niche. In this article, we individually place the signalling factors in their specified context, and explain their roles in the various phases of neovascularisation (see Part 1). (Neth Heart J 2008;16:337-43.)

Mesomeric divalent 1,1‘-(3-oxapentamethylene)-bridged bis(indenyl)lanthanidocenes, meso-[O(CH2CH2C9H6)2]Ln·(DME) (Ln = Sm (2),Yb (3)), have been synthesized by reduction of a mixture of rac/meso-[O(CH2CH2C9H6)2]LnCl·THF (Ln = Sm, Yb) with Na or reaction of LnI2 (Ln = Sm, Yb) with [O(CH2CH2C9H6K)2] in THF followed by recrystallization in DME. The structures of these meso, ansa-lanthanidocenes were determined by X-ray diffraction analysis. The factors that dictated the rac/meso selectivity are discussed. Nonbridged divalent lanthanide complexes (CH3OCH2CH2C9H6)2Ln^II (Ln = Sm (4), Yb (5)) were also synthesized for comparison by the reaction of LnI2 (Ln = Sm, Yb) with (CH3OCH2CH2C9H6)2K in THF. Stereoselective polymerization of methyl methacrylate with these divalent lanthanide complexes as single-component catalysts was preliminarily investigated.

A series of halogen-substituted 2,6-bis(imino)pyridyl ligands and their iron and cobalt complexes [{2,6-(2,6-X¹X²C6H3N&dbd;CCH3)2C5H3N}MCl2] (X¹ = X² = Br, M = Fe (1), Co (2); X¹ = X² = Cl, M = Fe (3), Co (4); X¹ = Cl, X² = H, M = Fe (5), Co (6); X¹ = Br, X² = H, M = Fe (7), Co (8); X¹ = I, X² = H, M = Fe (9), Co (10)) and [M{2,6-(2,6-X¹X²C6H3N&dbd;CCH3)2C5H3N}2]²⁺[MCl4]^2- (X¹ = F, X² = H, M = Fe (11)) have been synthesized. The molecular structures of complexes 1, 8, 9, 10, and 11 were determined by X-ray diffraction. Crystallographic analyses indicate that 1, 8, 9, and 10 are five-coordinate complexes, while 11 is an ion-pair complex with one six-coordinate iron center and one four-coordinate iron center. These metal coordinative complexes, activated by modified methylaluminoxane (MMAO), lead to highly active ethylene polymerization and/or oligomerization catalysts. The catalyst productivity and product properties crucially depended on the metal center and the halogen substituents on the aryl rings. The catalyst productivities are in the range of (0−73.0) × 10⁶ g/mol of cat·h. The species 11, having ion-pair structure, is inactive. In particular, the product molar masses were changed from high molar mass (Mw of 377 000) to low molar mass oligomers by varying the halogen substituents. NMR and thermal analyses reveal the polymer is highly linear. The oligomer products follow a Schulz−Flory distribution with high selectivity for linear α-olefins. The effects of reaction condition on the polymerization and oligomerization have also been studied.

Six five-coordinate difluoro-substituted 2,6-bis(imino)pyridyl iron and cobalt complexes, [{2,6-(2,X-F2C6H3N&dbd;CCH3)2C5H3N}MCl2] (X = 6, M = Fe (1), Co (2); X = 5, M = Fe (3), Co (4)); X = 4, M = Fe (5), Co (6)), were synthesized by reactions of the corresponding bis(imino)pyridyl ligands with FeCl2·4H2O or CoCl2 in tetrahydrofuran (THF). However, a reaction between 2,6-diacetylpyridinebis(2,6-difluoroanil) and FeCl2·4H2O in CH3CN provided the ion-pair complex [Fe{2,6-(2,6-F2C6H3N&dbd;CCH3)2C5H3N}2]²⁺[FeCl4]^2- (7) instead of a five-coordinate complex. The molecular structures of complexes 3 and 6 were determined by X-ray diffraction. The catalytic activities of complexes 1−7 for ethylene oligomerization were studied using modified methylaluminoxane (MMAO) as cocatalyst. At 60 °C and 10 atm of ethylene pressure, the iron complexes 1, 3, and 5 show very high activities:  4.07 × 10⁷, 9.33 × 10⁷, and 11.1 × 10⁷ g/((mol of cat.) h), respectively. The oligomers formed consist mainly of dimer, trimer, and tetramer, with approximately 90% of the products being in the range of C4−C8. The complexes 1, 3, and 5 also exhibit high selectivity for linear α-olefins:  >98% (complex 1) and >93% (complexes 3 and 5). The cobalt complexes 2, 4, and 6 and the ion-pair iron complex 7 are inactive for ethylene oligomerization.

The authors consider the nonlinear difference equation xn+1=αxn+xn-kf(xn-k),n=0,1,(0.1) where α∈(0,1), k ∈ 0,1, and f ∈ C1[[0,∞), [0,∞)] with f′(x) < 0. They give sufficient conditions for the unique positive equilibrium of (0.1) to be a global attractor of all positive solutions. The results here are somewhat easier to apply than those of other authors. An application to a model of blood cell production is given.

Reaction of the dimethylsilyl-bridged flourene cyclopentadiene ligand with 1 equiv of n-butyllithium or sodium hydride smoothly afforded the corresponding monoalkali-metal salts [(FluMe2Si)Cp]M·(THF)n (Cp = C5H4, Flu = C13H9) (M = Li (1), n = 0; M = Na (2), n = 1). Complexes 1 and 2 were characterized by single-crystal X-ray structural analyses. These revealed that both of them have similar linear polymeric structural aggregate types in the solid state. In complexes 1 and 2, the fluorenyldimethylsilyl groups attached to the cyclopentadienyl rings are arranged in gaps and oriented on the same side of the multideck chain.

A series of chiral 1,1‘-(3-oxapentamethylene)-bridged bis(indenyl) ansa-lanthanidocenes have been high stereoselectively synthesized. The reaction of YbCl3 with O(CH2CH2C9H6K)2 in THF provided a rac/meso mixture of [O(CH2CH2C9H6)2]YbCl(THF); the major diastereomer formed is racemic. The rac-[O(CH2CH2C9H6)2]YbCl(THF) (1) was isolated after recrystallization of a rac/meso mixture of [O(CH2CH2C9H6)2]YbCl(THF) in THF. Direct amidation (or alkylation) of the rac/meso lanthanidocene chloride mixtures in toluene provided solely pure racemic ansa-lanthanidocene amides [O(CH2CH2C9H6)2]LnN(SiMe3)2 (Ln = Y (2), Pr (3), Nd (4), Yb (5), Lu (6)) and pure racemic ansa-lanthanidocene hydrocarbyls [O(CH2CH2C9H6)2]LnCH2SiMe3 (Ln = Dy (7), Yb (8)). The structures of 1 and 5 were determined by X-ray diffraction. The amide and hydrocarbyl complexes are efficient single-component catalysts for methyl methacrylate polymerization. The effects of solvent and reaction temperature on the polymerization were studied. Very high molecular weight (Mn > 10⁶) iso-rich poly(MMA) was obtained at lower temperature, while low molecular weight moderately syndiotactic poly(MMA) was obtained at higher temperature. The polymerization behavior is proposed to be associated with rac/meso interconversion of the active center.

The new biscyclopentadienyl lutetium complex (η5:η1-C5H4CH2CH2PPh2)2LuCl was synthesized by the reaction of LuCl3(THF)3with lithium (2-diphenylphosphinoethyl)cyclopentadienide. Its behavior in solution was investigated by dynamic NMR spectroscopy. It was shown that the coordination of both phosphino groups to the lutetium center is retained over the whole temperature range studied. The barrier to pseudo-rotation for the trigonal bipyramid, which governs the intramolecular dynamics of this complex, was determined.

A series of new Cs-symmetric organolanthanocene chlorides, [R2Si(Flu)(R‘Cp)Ln(μ-Cl)]2 (Flu = C13H8, fluorenyl; Cp = C5H3) (R = Me, R‘ = H, Ln = Y (1), Lu (2), Dy (3), Er (4); R = Ph, R‘ = ^tBu, Ln = Y (5), Dy (6)), has been synthesized by the reaction of anhydrous lanthanide chloride with the dilithium salt of the ligand Me2Si(FluH)(CpH). Treatment of the resulting chlorides with ME(TMS)2 (M = Li or K, E = N, CH) gave the amide and hydrocarbyl derivatives Me2Si(Flu)(Cp)LnE(TMS)2 (E = N, Ln = Dy (7), Er (9); E = CH, Ln = Dy (8), Er (10)). X-ray structures of chloride compounds reveal unusual Cp−SiMe2−Cp bridging dimeric coordination. All of the amide and hydrocarbyl complexes show normal chelating structure and exhibit apparently intramolecular γ-agostic Ln−Me−Si interaction. These complexes are active for the polymerization of methyl methacrylate.

Consider the nonlinear difference equation [image omitted] where [image omitted] By using Liapunov's method, we establish some sufficient conditions for Eq. (0.1) to have a globally asymptotically stable positive equilibrium. Our results can be applied to some difference equations derived from mathematical biology.

The work reported here shows that steel fibres can reduce the expansion caused by alkali–aggregate reaction in concrete, hereby decreasing the resulting strength loss. The addition of 1–1·5% of steel fibres by volume allowed us to increase the alkali content by about 2 kg/m3. Under such conditions, the ultrasonic pulse velocity was found to be stable, and the expansion rate low, indicating only minor effects on the strength of the concrete, even though the concrete contained reactive aggregate and a high alkali content. More specifically, the effliciency of fibres for restricting expansion is governed by the size and geometric parameters of the fibres. The expansion rate was linearly related to the so-called fibre factor or fibre index, for otherwise similar alkali–aggregate reaction conditions.

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