Combustion characteristics of a charcoal slurry in a direct injection diesel engine and the impact on the injection system performance

The paper presents the research results pertaining to the renewable biomass charcoal-diesel slurries and their use as alternative fuels for combustion in diesel generating plants. The utilization of charcoal slurry fuel aims to reduce diesel oil consumption and would decrease fossil green house emissions into the atmosphere. The paper investigates the formulation, emulsification, sprays, combustion, injection system operation, and subsequent wear with charcoal-diesel slurries. In the research, cedar wood chips were used for the production of charcoal to be emulsified with diesel oil. The slurry’s viscosity of 27 cP achieved the target (<100 cP) and gave prospects of good spray atomization and while maintaining a high calorific value. Thermal analysis studies found that cedar wood will oxidize about 75% of its original mass by 450 °C. Charcoal slurry displayed a high vaporization rate of 75% by wt. at 300 °C. Engine investigations showed that the top combustion pressure at 1200 rpm and 100% load (7.8 brake mean effective pressure (bmep)) was 79 bar for diesel fuel and 78 bar for the charcoal slurry fuel. From the injection and heat release history was found an ignition delay of 1.7 ms for diesel that increased to 2.1 ms for the slurry fuel. A higher net heat release for charcoal slurry was observed, up to 180 J/crank angle degrees (CAD) compared with the diesel at 145 J/CAD The maximum combustion temperature reached 2300 K for diesel and 2330 K for slurry. The heat fluxes for both fuels have similar values and trends during the entire cycle showing the good compatibility of charcoal slurry with a diesel type combustion and low soot radiation. The exhaust temperatures were about 40-50 °C higher for charcoal slurry at 19° before top dead center (BTDC) injection timing. The engine’s bsfc increased as expected due to the lower heating value of the slurry fuel. The smoke Bosch no. was lower for the slurry fuel at any load, and is believed that the oxygen from the charcoal had a beneficial effect. The measured emissions of slurry fuel were better at 13° BTDC than those of diesel fuel with the original engine settings and the remaining 6-10% oxygen content in the charcoal is thought to have a paramount role in helping the diffusion type combustion and diminishing the particulate matter formation. As the load was increased, the amount of time it took to notice a decline in engine efficiency decreased. This was due to the injector sticking open which was seen by a sharp increase in the exhaust temperature. The internal flow into the injector had the tendency to form deposits on the injector’s seat that were critical to the functionality of the injector. In order to alleviate this problem, a reduced charcoal particle size together with a new injector design were produced resulting in stable engine efficiency at 50% load for a period of 90 min without injector sticking. Even with improvements, the needle’s seat into the injector body showed an accelerated wear 4-8 times faster than that in normal operation with diesel fuel and this cannot be sustained for long operational cycles. The investigations have proven that the new charcoal-diesel slurry can produce adequate sprays and burn with very good results in a direct injection diesel engine. The critical aspect of operation is the internal flow into the injector with the tendency to form deposits and wear in the injector.     

Theoretical analysis of grain boundary liquation in heat affected zone of Inconel 718 alloy. Study of laser weldability of Ni‐base superalloys (3rd Report)

In this work, with the aid of the implicit gradient method, the fatigue behaviour of different types of arc-welded joints was analysed. The structural parts, made of steel, were modelled as three-dimensional solids without applying any geometric exemplification, directly calculating the fatigue life numerically. The advantage offered by this approach is that of being able to maintain the unvaried calculation procedure regardless of the type of joint in question. Moreover, adopting the gradient method, there is no obligation to impose particular rules for the creation of the calculation mesh on the finished elements.     

Enhancement of SPARC (osteonectin) synthesis in arthritic cartilage. Increased levels in synovial fluids from patients with rheumatoid arthritis and regulation by growth factors and cytokines in chondrocyte cultures

OBJECTIVE: To investigate the roles of SPARC (secreted protein, acidic and rich in cysteine) (osteonectin) in arthritis, using cartilage and synovium specimens and synovial fluids (SF) from patients with rheumatoid arthritis (RA) or osteoarthritis (OA), and to examine the effects of cytokines, growth factors, and hormones on SPARC synthesis by chondrocytes in culture. METHODS: SPARC in cartilage and synovium was immunostained with monoclonal antibodies. SPARC synthesis by cultured chondrocytes was measured by Northern blot analysis, immunoblotting, and sandwich enzyme-linked immunosorbent assay. RESULTS: SPARC was identified in numerous chondrocytes in the superficial and middle zones and in regenerating chondrocytes of RA and OA joints, whereas such staining was absent in these zones of normal cartilage, except for weak signals from a few chondrocytes in the deep zone. In addition, SPARC synthesis was enhanced in synovial cells of RA and OA joints. The average SPARC level in SF was 10-fold higher in the RA than in the OA population. In rabbit articular chondrocyte cultures, administration of transforming growth factor beta 1 (TGF beta 1) and bone morphogenetic protein 2 increased SPARC levels at 24-48 hours, whereas interleukin-lbeta (IL-1 beta), IL-1 alpha, tumor necrosis factor alpha, lipopolysaccharide, phorbol myristate acetate, basic fibroblast growth factor, and dexamethasone decreased SPARC levels at 24-72 hours. TGF beta increased SPARC messenger RNA (mRNA) levels at 24 hours, whereas IL-1 beta caused a marked decrease in SPARC mRNA levels at 24 hours. Furthermore, IL-1 decreased the glycosylation of SPARC. CONCLUSION: These findings suggest that various growth factors and cytokines, including TGF beta 1 and IL-1 beta, regulate the production of SPARC by chondrocytes at pre- and posttranslational levels, and that SPARC synthesis is markedly enhanced in arthritic joints.     

Determination of intrinsic viscosity of fractionated pitches and discussion on the shape and size of pitch molecules

Intrinsic viscosity η of fractionated petroleum pitches in benzene solution was measured by using a capillary viscometer of Ubbelohde type. Molecular weight fractionation of the pitch was successfully carried out by using non-polar solvents, benzene and n-hexane. The dependence of η on molecular weight ?M_n is found to be as ?M_n^{$\text{1}\text{10}$}, from which the shape of the pitch molecules is concluded to be three-dimensional, rather than planar. Some discussion of the hydrodynamically equivalent size and of the configuration of the pitch molecules is given.     

Involvement of dendritic adhesion molecule telencephalin in hippocampal long-term potentiation

Telencephalin (TLCN) is a cell adhesion molecule belonging to the immunoglobulin superfamily whose expression is restricted to neurons within the most highly developed brain segment, telencephalon. Immunoelectronmicroscopic study revealed that in the hippocampal CA1 region, TLCN was localized at the surface membrane of postsynaptic spines of pyramidal cell dendrites but not at that of axonal terminals. Blocking of TLCN function using anti-TLCN antibody or recombinant soluble TLCN protein caused a striking suppression of the long-term potentiation (LTP) at the Schaffer collateral-CA1 synapses. The suppression was observed even when the blocking was initiated immediately after the tetanic stimuli. These observations suggest a role for TLCN-mediated cell-cell interactions as a key step in the development of LTP.     

热时效对X80钢级埋弧焊管变形能力的影响

X80钢级管线钢管的应用促进了管线运行压力的提高,因此对基于应变的管线设计(SBD)来说,有必要对X80钢级埋弧焊管的应变能力进行测定。在对应变能力的测定中,热时效对屈服现象的影响便成为其重要因素。本次研究中,进行了全尺寸钢管弯曲试验和有限元分析(FEA),用以弄清热时效对X80钢级UOE直缝焊管应变能力的影响;并采用有限元分析法对应变能力与应变要求之间的关系进行了研究。     

Formation mechanism of asymmetric porous polymer films by photoinduced phase separation in the presence of solvent

Photoinduced phase separation in the presence of a nonreactive volatile solvent provides a simple, light-tunable, and cost-effective route for fabrications of porous polymer films. Here, we show that the short-time (<10 s) ultraviolet irradiation of a photoreactive solution film promotes particular asymmetries in the composition and porosity across the thickness. Confocal Raman spectroscopy revealed that the compositional asymmetry is maximum at a certain critical light intensity. We discuss the film formation mechanism based on the light-driven diffusion of the solvent and monomer. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47867.     

Electrochemical behavior of Au nanoparticle deposited on as-grown and O-terminated diamond electrodes for oxygen reduction in alkaline solution

Au nanoparticle was electrochemically deposited on both as grown and oxygen-terminated (O-terminated) boron-doped diamond (BDD) films. The surface coverages of Au nanoparticle were 0.07 and 0.18 corresponding to the areas of Au 0.012 and 0.029 cm², respectively, as noted from linear sweep voltammetry. The SEM studies indicated different morphologies of Au deposition such as random distribution of small spherical particles at both the grain boundaries and the facets on the as grown diamond film and clusters principally on the cross edges of two facets on the O-terminated diamond. The electrochemical behavior for oxygen reduction was examined using differential pulse voltammetry (DPV), which confirmed the higher catalytic efficiencies of Au deposited as grown and O-terminated BDD electrodes when compared to a polycrystalline Au electrode. Moreover, the mechanism of Au nanoparticle deposited BDD films for the oxygen reduction was investigated by ac impedance and hydrodynamic voltammetric methods.     

Recent Insights into Human Endometrial Peptidases in Blastocyst Implantation via Shedding of Microvesicles

Blastocyst implantation involves multiple interactions with numerous molecules expressed in endometrial epithelial cells (EECs) during the implantation window; however, there is limited information regarding the molecular mechanism underlying the crosstalk. In blastocysts, fibronectin plays a major role in the adhesion of various types of cells by binding to extracellular matrix proteins via the Arg-Gly-Asp (RGD) motif. In EECs, RGD-recognizing integrins are important bridging receptors for fibronectin, whereas the non-RGD binding of fibronectin includes interactions with dipeptidyl peptidase IV (DPPIV)/cluster of differentiation (CD) 26. Fibronectin may also bind to aminopeptidase N (APN)/CD13, and in the endometrium, these peptidases are present in plasma membranes and lysosomal membranes. Blastocyst implantation is accompanied by lysosome exocytosis, which transports various peptidases and nutrients into the endometrial cavity to facilitate blastocyst implantation. Both DPPIV and APN are released into the uterine cavity via shedding of microvesicles (MVs) from EECs. Recently, extracellular vesicles derived from endometrial cells have been proposed to act on trophectoderm cells to promote implantation. MVs are also secreted from embryonal stem cells and may play an active role in implantation. Thus, crosstalk between the blastocyst and endometrium via extracellular vesicles is a new insight into the fundamental molecular basis of blastocyst implantation.     

Dynamics of a ferroelectric liquid crystal with a naphthalene ring during electric-field-induced switching studied by time-resolved infrared spectroscopy combined with two-dimensional correlation spectroscopy

The dynamics of a ferroelectric liquid crystal with a naphthalene ring (FLC-3) during the electric-field-induced switching between two surface-stabilized ferroelectric liquid crystal states were investigated by time-resolved infrared (IR) spectroscopy combined with two-dimensional (2D) correlation spectroscopy. Time-resolved IR spectra of FLC-3 in a planar-aligned cell were measured as a function of the polarization angle range from 0 degree to 180 degrees under a rectangular electric field of +/- 40 V with a 5 kHz frequency in the smectic-C* (Sm-C*) phase at 137 degrees C. From these spectra we explore details about the reorientation process of the alkyl chains, the core, and the large C=O dipole moments of FLC-3 at all the delay times. The 2D correlation spectroscopy was applied to the polarization-angle-dependent spectra for different delay times and to the time-resolved spectra at certain polarization angles to reveal the relative orientation of the C=O groups and the core moiety during the electric-field-induced switching. It was found from the present study that the relative orientation of the C=O groups and the core remains unchanged during the initial period of the reorientation, while it is reversed at a certain moment and then kept unchanged again. Moreover, the alkyl chains, C=O groups, and core moieties posses different dynamics during the fast course of electric-field-induced switching by analyzing time-resolved spectra.