Maximum Expansion Rate Research Articles

Active roof-contacted combined backfill mining technology based on a modified magnesium slag-based cementitious material

Backfill mining technology is an inevitable choice for sustainable green mining. Full roof-contact of backfill is a key issue to ensure the long-term stability of the backfill mining technology, but no effective measures have been proposed. Based on the expansion characteristics of the modified magnesium slag-based filling material (MCM) and the shrinkage characteristics of the ordinary cement-bonded filling material (CFM), an active roof-contacted combined backfill mining technology (MCM-CFM) was proposed. The expansion characteristics and the uniaxial compressive strength (UCS) of the modified magnesium slag-based cementitious material (MC) were compared and analyzed. And the analytical expressions of the main control parameters as the axial force and the filling height of the backfill were derived, with or without lateral restraints. Then the sensitivity and the influence rule of the parameters were also investigated. The results show that: (1) the expansion rate of MC can reach 0.21% and increases rapidly in the early stage. At 28d and 40d, 84% and 95% of the total expansion deformation are reached, respectively, and the maximum expansion rate is 0.21%. (2) With or without lateral restraints, the height ratio of the upper and the lower filling parts is about 0.72 or 0.18, respectively. (3) The force subjected on the backfill is mainly controled by the parameters of the filling width, the elastic modulus and the expansion rate. (4) With or without lateral restraints, the height ratio of the two filling materials is controlled by the elastic modulus, the density or the elastic modulus, the Poisson’s ratio, the expansion rate, respectively. MCM-CFM can solve the problem of active roof-contact for backfill mining technology, and has the potential for large-scale application in mine backfilling.

Mechanical Properties and Durability of Steel Slag-mineral Powder-coal Gangue Mixture by Uniform Design for Pavement Base

To realize the utilization of industrial solid waste resources and solve the shortage problem of pavement materials, this paper uses steel slag, mineral powder, and coal gangue to prepare a mixture. A uniform test with 2 factors and 6 levels was designed. Through regression analysis, response surfaces were established to study the mechanical properties of the coal gangue mixture. The hydrated products at different ages were microscopically analyzed by XRD and SEM. The durability including freeze-thaw cycles, dry and wet cycles, and immersion expansion rate were researched. The results show that the 7d unconfined compressive strength of the mixture reaches 2.14 – 6.46 MPa, with a 180d resilience modulus of 954 – 1098 MPa, and a 180d splitting tensile strength of 0.66 – 0.83 MPa. With the increase of steel slag content, the 7d unconfined compressive strength of the mixture first decreases and then increases. The content of mineral powder is positively correlated with the 7d unconfined compressive strength. The 180d compressive resilience modulus decreases first and then increases with the increase of steel slag and mineral powder content. The 180d splitting tensile strength is positively correlated with the content of steel slag and mineral powder. The mixture is less affected by freeze-thaw cycles, with mass loss rates of only 1.77 % – 2.13 %. The mass loss rate of the admixture is 0.87 % – 0.99 % after 10 dry and wet cycles, and the strength is slightly improved. The maximum expansion rate of the mixtures immersed in water for 10d is only 0.28 %. The hydrated reaction between steel slag, mineral powder and coal gangue promotes the formation of more hydration products such as AFt, C-S-H, CaAl2(SiO4), and Ca(OH)2. The C-S-H and CaAl2(SiO4) are intertwined into a dense network to wrap Ca(OH)2, which improves the compactness of the mixture and effectively resists the freeze-thaw expansion stress. The steel slag-mineral powder-coal gangue mixture meets the requirements of relevant norms and can be well used in pavement bases.

Longitudinal MRI of the developing ferret brain reveals regional variations in timing and rate of growth.

Normative ferret brain development was characterized using magnetic resonance imaging. Brain growth was longitudinally monitored in 10 ferrets (equal numbers of males and females) from postnatal day 8 (P8) through P38 in 6-d increments. Template T2-weighted images were constructed at each age, and these were manually segmented into 12 to 14 brain regions. A logistic growth model was used to fit data from whole brain volumes and 8 of the individual regions in both males and females. More protracted growth was found in males, which results in larger brains; however, sex differences were not apparent when results were corrected for body weight. Additionally, surface models of the developing cortical plate were registered to one another using the anatomically-constrained Multimodal Surface Matching algorithm. This, in turn, enabled local logistic growth parameters to be mapped across the cortical surface. A close similarity was observed between surface area expansion timing and previous reports of the transverse neurogenic gradient in ferrets. Regional variation in the extent of surface area expansion and the maximum expansion rate was also revealed. This characterization of normative brain growth over the period of cerebral cortex folding may serve as a reference for ferret studies of brain development.

Chemical deformation and mass change of metakaolin-based geopolymer grouting material in sulfate environments

Metakaolin (MK) and waterglass (WG) with a modulus of 1.3 were mixed to prepare MK-based geopolymer grouting materials (MKGPGM) with different alkalinity (concentration of sodium oxide in modified WG by mass of MK of 11 wt%, 12 wt% and 13 wt%). The linear expansion, mass change, mechanical properties and microstructure of the specimens were investigated after being immersed in pure water and sodium sulfate solutions with a concentration of 1–4 wt% for 90 days. The results showed that the main gel products were sodium silicoaluminate hydrate gels. Gypsum and ettringite were not detected in the specimens. The MKGPGM showed slight expansion first, followed by a micro-shrinkage. When the mass concentration of sodium oxide was 12 wt%, the maximum expansion rate was less than 0.12%. The MKGPGM showed a small increase in mass, essentially unchanged compressive strength and good anti-sulfate corrosion performance.

Controllable Design of Structural and Mechanical Behaviors of Al–Si Foams by Powder Metallurgy Foaming

Silicon (Si) has a significant influence on the cellular structure and microstructure of the aluminum (Al) foams, which in turn will notably affect their mechanical responses. Herein, the Al–Si foams are fabricated via a novel powder metallurgy foaming approaches with multiple Si contents to investigate the role of Si concentrations on the structural and mechanical properties. The results show that the certain contents of Si can not only delay the expansion process, but also increase the maximum expansion rate to improve the cellular structure. Specifically, the AlSi7 foams process the optimal comprehensive compressive properties of yield stress (4.36 MPa), plateau stress (6.02 MPa), and energy absorption capacity (3.47 MJ m−3) with the relative density of 0.15. However, excessive Si can decrease the expansion rate and deteriorate the cellular structure. Moreover, the deformation mode of the Al foams during compressive process converts from plastic mode to brittle mode by the adding of Si. Generally, the AlSi7 foams possess an excellent trade‐off between toughness and brittleness and exhibit the optimal mechanical responses.

Cryogenic deformation behavior of 6061 aluminum alloy tube under biaxial tension condition

Cryogenic forming has been proposed for the fabrication of complex aluminum alloys tubular components to overcome the shortcomings of traditional forming processes. It is difficult to evaluate the cryogenic biaxial deformation behavior. In this study, a novel cryogenic hydro-bulging device was established to evaluate cryogenic deformation behavior and verify the feasibility of the new forming process. The cryogenic biaxial stress-strain relations were determined using a new analytical model to quantitatively characterize the hardening behavior. The cryogenic deformation mechanism was revealed by microstructure characterization. It is found that the maximum expansion rate of 6061 aluminum alloy tube at − 196 ℃ increases to 34.0% ± 0.6%, being 99.8% higher than that at room temperature. The obtained cryogenic biaxial flow curve exhibits the significantly improved plasticity and hardening ability with a strain hardening exponent of 0.43 at − 196 ℃. The high cryogenic strain hardening rate contributes to the stable uniform deformation. The improved cryogenic plasticity is associated with the diminished dislocations accumulation at grain boundaries. The enhanced cryogenic hardening ability is attributed to the impeded movable dislocations slip. The research demonstrates that cryogenic medium pressure forming has great potential for the fabrication of complex aluminum alloy tubular components. • A novel cryogenic hydro-bulging device was established for evaluating the cryogenic biaxial deformation behavior oftubes. • The cryogenic biaxial mechanical properties and hardening behavior were quantitatively evaluated by a new analytical model. • Excellent cryogenic biaxial formability can be obtained, contributing to the fabrication of complex tubular parts. • Microstructure was characterized to reveal the cryogenic deformation mechanism.

Changes in the Invasion Rate of Prosopis juliflora and Its Impact on Depletion of Groundwater in the Northern Part of the United Arab Emirates.

Prosopis species were introduced to the United Arab Emirates (UAE) region for desert greening. However, the species now pose a great threat to the native plant diversity. This study used high-resolution satellite imagery (1990–2019) to understand the history and current distribution of Prosopis species and their impact on fresh groundwater. The results show that the Prosopis invasion in the study area reached its maximum expansion rate in 2019 and covered an area of about 16 km2 compared to 0.2 km2 in 1990. The areas near Sharjah Airport, Umm Fannan, and Al Talla, located at a lower elevation of the sand dune area, are heavily invaded. Prosopis groundwater requirement derived using evapotranspiration shows that groundwater consumption has changed drastically after 2010 and consumed about 22.22 million m3 of groundwater in 2019, which is about a 7372% increase in groundwater consumption from the year 1990 to 2019. The results can be useful for setting up a management plan for the sustainable use of this species in the UAE region in particular and other similar countries in the arid land regions that are suffering from freshwater depletion because of Prosopis invasion.

A simulation study on expansion of a small intestine model reactor

In vitro digestion models and bionic reactors are usually made of soft elastic materials, which can be expanded in certain cases. However, little is known about the expansion of these models and reactors and the effect of the expansion on the fluid flow and concentration distribution. In this study, the expansion of a simplified small intestine model reactor is investigated using COMSOL Multiphysics. The results showed that the expansion rate significantly increased as Young’s modulus decreased; the influence of Poisson’s ratio on the expansion of the model with similar materials can be neglected. The model’s expansion rate increases significantly as the inlet velocity and fluid viscosity increase. However, the expansion rate decreases as the model’s spherical coefficient increases. The maximum expansion rate of the model in the given scope of the factors can be predicted using the regression equation obtained from Response Surface Methodology (RSM). It can also be concluded that the higher maximum expansion rate caused the velocity in radial and axial directions to be reduced and the pressure slightly reduced. Meanwhile, the model’s expansion would result in a nonuniform concentration distribution of the fluid in the model, which leads to a longer residence time of the fluid.

Estimation of the Recent Expansion Rate of Ruspolia nitidula (Orthoptera) on a Regional and Landscape Scale

Simple SummaryRecent changes in insect distribution are consistent with the effects of climate and habitat change. The bushcricket Ruspolia nitidula has expanded in Western and Central Europe in recent decades. In the Czech Republic, R. nitidula was recorded in 2006 after ca. 50 years of absence. Using available occurrence data from professionals and citizens we estimated the R. nitidula expansion rate from 2006 to 2020 in the Czech Republic. For comparison, we monitored in detail expansion at the areal margin in the Odra River basin from 2016 to 2020. To estimate the expansion rates, we used three different methods of spatial analysis, including least-cost path analysis with habitat suitability. The estimated maximum expansion rate ranged from 13.8 to 16.2 km/year based on occurrence data at the country level and from 11.1 to 11.7 km/year based on the monitoring in the Odra River basin.Recent changes in insect distribution are consistent with the expected interacting effects of climate and habitat change. The orthopteran Ruspolia nitidula has expanded its area of distribution in Western and Central Europe in recent decades. Because males emit a sound that is easily detected at a distance of up to 40 m, it is possible to detect spreading individuals and to therefore document routes and rates of spread. Using occurrence data at the landscape scale and three methods, including least-cost path analysis with habitat suitability, we estimated the R. nitidula expansion rate from 2006 to 2020 in the Czech Republic; this involved estimating distances between two origin occurrences in 2006 and two occurrences on the area margin in 2020. For comparison, we directly monitored expansion based on detection of singing males at the regional scale at the areal margin in the Odra River basin (2016–2020). The estimated maximum expansion rate ranged from 13.8 to 16.2 km/year based on occurrence data at the landscape scale and from 11.1 to 11.7 km/year based on the monitoring of males in the Odra River basin. To our knowledge, this is the first report of the direct monitoring of individual spreading males to detect changes in the distribution of an orthopteran.

Polydopamine enwrapped titanium dioxide-assisted dispersion of graphene to strength fire resistance of intumescent waterborne epoxy coating

Herein, polydopamine (PDA) with excellent hydrophilicity and strong adhesion was used to decorate the TiO2 nanoparticles. Then, the obtained PDA modified TiO2 was directly combined with graphene (Gr) through the π-π non covalent interaction to improve the water dispersion stability of hydrophobic Gr. After that, the above hybrids (TPG) was added to the intumescent waterborne epoxy coating to explore its fire protection ability. The fire resistance of the intumescent composite coating was tested by big panel method test, furnace test and thermogravimetric analysis (TGA). And the structure and morphology of the inorganic residual char were analyzed by FT-IR, XPS, SEM and XRD technology. The results showed that the introduction of PDA effectively improved the oxidation resistance of the composite coating, while TiO2 nanoparticles enhanced the stability of the char layer. More importantly, the incorporation of Gr further enhanced the barrier effect of char layer on thermal and mass. The 1.5 % TPG based sample exhibited the maximum expansion rate (8.61), the highest carbon residue (29.7 %) and the best heat insulation property due to the synergistic fire prevention effect of PDA, TiO2 and Gr nanosheets.

Evolution and Influencing Factors of Township Spatial Form: A Two-Dimensional Perspective

The countryside is the habitat of food, ecology, and culture, and the indispensable basis for human survival and development. Assessing the spatial and temporal evolution of rural settlements contributes to the promotion of rural scientific developments. This study used the fractal theory, center-of-gravity model, and spatial syntax to analyze the spatial and temporal evolution of Shenyang Ciyutuo Subdistrict and its influencing factors based on geospatial data from 2009‒2019, from the perspectives of internal characteristics and external morphological changes. In terms of the external characteristics, from 2009‒2019, the compactness index increased from 0.414 to 0.454, the expansion rate increased from 1.17% to 3.11%, and the expansion intensity increased from 0.05% to 0.15%. From 2014‒2019, the western part of the subdistrict experienced the maximum expansion rate and expansion intensity. The center-of-gravity of the construction land shifted to the west and southwest. The internal characteristics of land use depended on geographical conditions. Clusters of rural settlements were formed in a north-south direction due to the topography and along the riverside in a band-like manner. From 2009‒2019, the integration level of the subdistrict improved and the scale and number of integration axis increased, forming a multicore tree-shaped structure. Pearson’s correlation analysis showed that urbanization is the main factor affecting the spatial and temporal land-use evolution, with transportation convenience, industrial park, and proximity to the river having little effects. This study provides a theoretical basis for the development of Ciyutuo Subdistrict and provides a reference for the development of similar commercial towns.

Effect of process parameters on the functional and physicochemical properties of extrudates enriched with starch-based nut flour

Widening the range of products produced on the basis of agricultural raw materials and improving the quality of these products and increasing their nutritional value ”‹”‹represent urgent challenges. Therefore, the production of new mass consumption products with high nutritional and biological value brings to the fore the use of local nut flour as an enriching supplement in innovative technological processes. The high nutritional value of nuts (nuts, walnuts, and peanuts) is due to their chemical composition, including lipids, a large amount of soluble proteins that are well absorbed by the human body, sufficiently large quantities of vitamin B1 and a small amount of vitamins PP and E. It is known that in peanut grains, lipids have a balanced composition of fats and acids, as well as sufficiently large amounts of essential amino acids, which makes their protein composition closer to that of animal proteins. This study considers the influence of thermoplastic extrusion parameters on the functional and physicochemical properties of extrudates in their formation process. The technological and design parameters of the process and their variation ranges are based on studies conducted on model systems. The ratio of the extrusion mixture components (formulation) is also developed. Based on the methodology for multifactorial experimental design, the variation of the volume weights, expansion rates, and mechanical specific energy expenditure of porous extrudates enriched with starch-based nut flour is studied. It has been established that the best quality indicators of the products are achieved with the minimum volume weight and the maximum expansion rate.

SINGLE CELL RNA-SEQ REVEALED CLONAL REPOPULATION DYNAMICS BY MOUSE HEMATOPOIETIC STEM CELLS

Single hematopoietic stem cells (HSCs) can reconstitute the entire hematopoietic system after transplantation. However, how HSCs reconstitute hematopoietic cells is poorly understood. We used single-cell RNA sequencing (scRNA-seq) to identify cells and study their kinetics. Single CD201+CD150+CD48-Lineage- cells from GFP-transgenic B6 mice were transplanted into lethally irradiated mice with competitor cells. From BM and spleen of recipients, single GFP+ cells were isolated 2-3 weeks after transplantation, and single GFP+ CD34-KSL cells were isolated 1, 4, 8, and 12 months after transplantation. These cells were subjected to scRNA-seq. Based on transcriptome-defined (t) cell types under homeostasis, donor-derived single cells were classified into tHSCs, tMPPs, tCPs (committed progenitors, CMP, MEP, GMP and CLP), tMEs, tGMs, and tLymphocytes (B, T, and NK cells). We detected tMEs and tGMs as the major populations 2 weeks after transplantation. We first detected tHSCs 3 weeks after transplantation. Based on the absolute number of tHSCs, their maximum expansion rate was detected between 3 and 4 weeks after transplantation. We also detected tMEs, tGMs, and tLymphocytes from 1 to 12 months, and these cells increased more 8 and 12 months after transplantation. Donor cells were assigned as a and b cells based on the ratio of myeloid cells (GM) and lymphoid cells (T+B) in peripheral blood 4 month after transplantation. a cells gave rise to tHSC1 and 2 while b cells gave rise to tHSC1, 2, and 3. These data supported the original function definition of these cells. In summary, this study not only illustrates the early differentiation phase, followed by the expansion phase of HSC after transplantation. Deep analysis of the key regulation network in clonal hematopoiesis will provide more information for molecular mechanism of HSC self-renewal and lineage differentiation.

Monitoring Long-term Mangrove Shoreline Changes along the Northern Coasts of the Persian Gulf and the Oman Sea

Generally, investigating changes in mangrove shorelines is an important step to evaluate whether mangrove ecosystems are expanding or contracting. In this study, the rates of change of mangrove boundaries were investigated along the coasts of the Persian Gulf and the Oman Sea, over a 30-year period. Seaward edges of mangrove forests were extracted from Landsat images of the years 1986, 2000 and 2016 and the Digital Shoreline Analysis System (DSAS) Software was used to implement the Linear Regression Rate (LRR) method to quantify the rates of boundary changes. On average, areas that experienced boundary expansion progressed by 2.55 m yr-1 and those that experienced contraction regressed by -0.38 m yr-1. The maximum rate of expansion was 25.91 m yr-1 and the maximum rate of contraction was -22.45 m yr-1. Mangroves located on the coasts of the Persian Gulf exhibited differential rates of progression and regression at their borders, with expansion rates increasing in an eastward direction toward the coasts of the Oman Sea. However, on the eastern coasts of the Oman Sea, mangroves are characterized by contraction and erosion.

Redshift remapping and cosmic acceleration in dark-matter-dominated cosmological models

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This relation is not a fundamental theory and thus observational determination of this function (redshift remapping) should be regarded as an insightful alternative to holding its standard form in analyses of cosmological data. Here we present non-parametric reconstructions of redshift remapping in dark-matter-dominated models and constraints on cosmological parameters from a joint analysis of all primary cosmological probes including the local measurement of the Hubble constant, Type Ia supernovae, baryonic acoustic oscillations (BAO), Planck observations of the cosmic microwave background (CMB) radiation (temperature power spectrum) and cosmic chronometers. The reconstructed redshift remapping points to an additional boost of redshift operating in late epoch of cosmic evolution, but affecting both low-redshift observations and the CMB. The model predicts a significant difference between the actual Hubble constant, h=0.48+/-0.02, and its local determination, h_obs=0.73+/-0.02. The ratio of these two values coincides closely with the maximum expansion rate inside voids formed in the corresponding open cosmological model with Omega_m=0.87+/-0.03, whereas the actual value of the Hubble constant implies the age of the Universe that is compatible with the Planck LambdaCDM cosmology. The new dark-matter-dominated model with redshift remapping provides excellent fits to all data and eliminates recently reported tensions between the Planck LambdaCDM cosmology, the local determination of the Hubble constant and the BAO measurements from the Ly-alpha forest of high-redshift quasars.

Evaluation of Foaming Behavior of Glass Melts by High‐Temperature Microscopy

Optical monitoring techniques can record in situ the size of glass samples during a dynamic heating process. This allowed us to study the sintering and expansion rate of panel glass from cathode ray tube using MnO2 as foaming agent. We show the maximum expansion rate of glass melt foaming (in situ value) correlates to 50% closed porosity, and we define a universal temperature window for foaming glass melts based on the sintering–expansion curves obtained with a heating microscope. The sample size obtained at the maximum expansion rate can be used to quickly evaluate various foaming parameters such as type and concentration of foaming agent, glass composition, and particle size to obtain foam glass with high porosity and closed pores. Using this approach, we show that the foaming of bottle glass is preferentially conducted at a SiC concentration of 1‒4 wt%.

Birefringence parameter available for quantitative analysis of human zona hardness

This study was designed to investigate whether a non-invasive birefringence parameter, determined using the Oosight™ imaging system, is useful for estimating the hardness of human zona pellucida (ZP). The value for retardance (R) × thickness (T), but not R or T alone, of ZP was positively correlated (r = 0.92, p < 0.0001) with its hardness estimated by the time required for a 0.1% protease solution to solubilize ZP at 37 °C. In a model experiment to induce ZP puncture by Fluorinert™ fluid microinjection (sham-hatching), the R × T value at the punctured site was positively correlated (r = 0.78, p < 0.01) with the hardness of the ZP as estimated by the maximum expansion rate. The R × T values of ZP in in vitro fertilization-derived embryos (21.6 ± 7.5) and intracytoplasmic sperm injection-derived embryos (20.8 ± 6.3) were significantly higher than that in unfertilized metaphase II oocytes (16.6 ± 6.1; p < 0.05). The R × T value after in vitro hatching of viable blastocysts (10.8 ± 6.2) was significantly lower than that of unexpanded morulae and early blastocysts (19.0 ± 4.0; p < 0.05), while the value of expanding blastocysts (15.3 ± 4.1) was intermediate. In conclusion, hardness of human ZP can be estimated non-invasively by birefringence-based microscopic observation.

Self-consistent equation of plant cell growth

We introduce a transcendental equation, describing the subsequent stages of plant cell/organ growth. Starting from empirically verified conclusions originating from the central limit theorem we also insert the influence of temperature on elongation growth to receive a time-dependent equation of growth parameterized by temperature. This self-consistent equation evolves with time using three cardinal parameters: t0, T0 and V0. They represent the time of maximum expansion rate, the growth optimum temperature and the corresponding volume, respectively. Experimental determination of these cardinal values enables evaluation of the dynamic extensibility coefficient Phi=PhiT(t) in time and temperature domain.

Influence of mouth status and water level on the macrophytes in a small temporarily open/closed estuary

The monthly responses of macrophytes in the East Kleinemonde Estuary were examined in relation to changes in physical factors between March 2006 and March 2007. The East Kleinemonde is a small temporarily open/closed system where the mouth breaches in response to high water levels (>2 m amsl) or following high river inflow. On breaching there is a rapid drop in water level that causes the submerged macrophytes to be exposed and they die as a result of desiccation. Salt marsh plants then establish in the vacant habitat. Correlation analysis showed that water level and duration of inundation influenced macrophyte cover abundance. Inundation for 3 months caused die-back of intertidal salt marsh. Under open and tidal conditions, intertidal salt marsh increased at a maximum monthly expansion rate of 25% change in cover. Supratidal salt marsh expanded at maximum monthly rates of 33% change in cover. Because of its position at a relatively high elevation compared to other vegetation, supratidal salt marsh was only affected by water levels of >1.8 m amsl and only after being inundated for 1–2 months. Submerged macrophytes developed in inundated areas when stable water levels were present for longer than 2 months at a monthly maximum expansion rate of 23% cover change. In this study macrophytes responded quickly to water level fluctuations and indicate that monthly monitoring is needed to provide an understanding of macrophyte response. This is the first study that reports on rates of macrophyte habitat development in temporarily open/closed estuaries. These data can be used in mouth management plans and freshwater requirement studies to predict the growth and establishment of a diversity of macrophyte habitats.

Delaunay Tessellation Field Estimator analysis of the PSCz local Universe: density field and cosmic flow

We apply the Delaunay Tessellation Field Estimator (DTFE) to reconstruct and analyse the matter distribution and cosmic velocity flows in the local Universe on the basis of the PSCz galaxy survey. The prime objective of this study is the production of optimal resolution 3D maps of the volume-weighted velocity and density fields throughout the nearby universe, the basis for a detailed study of the structure and dynamics of the cosmic web at each level probed by underlying galaxy sample. Fully volume-covering 3D maps of the density and (volume-weighted) velocity fields in the cosmic vicinity, out to a distance of 150 h(-1) Mpc, are presented. Based on the Voronoi and Delaunay tessellation defined by the spatial galaxy sample, DTFE involves the estimate of density values on the basis of the volume of the related Delaunay tetrahedra and the subsequent use of the Delaunay tessellation as natural multidimensional (linear) interpolation grid for the corresponding density and velocity fields throughout the sample volume. The linearized model of the spatial galaxy distribution and the corresponding peculiar velocities of the PSCz galaxy sample, produced by Branchini et al., forms the input sample for the DTFE study. The DTFE maps reproduce the high-density supercluster regions in optimal detail, both their internal structure as well as their elongated or flattened shape. The corresponding velocity flows trace the bulk and shear flows marking the region extending from the Pisces-Perseus supercluster, via the Local Superclusters, towards the Hydra-Centaurus and the Shapley concentration. The most outstanding and unique feature of the DTFE maps is the sharply defined radial outflow regions in and around underdense voids, marking the dynamical importance of voids in the local Universe. The maximum expansion rate of voids defines a sharp cut-off in the DTFE velocity divergence probability distribution function. We found that on the basis of this cut-off DTFE manages to consistently reproduce the value of Omega(m) approximate to 0.35 underlying the linearized velocity data set.