Predicting Blast-induced Ground Vibration in Quarries Using Adaptive Fuzzy Inference Neural Network and Moth–Flame Optimization

Natural Resources Research - Blasting is a first preparatory stage that plays a fundamental role in the subsequent operations of an open pit mine. However, its adverse effects can seriously affect...     

The Mid-IR view of interacting galaxies

In this paper, we present ISOCAM mid-IR broad band images and spectraof three well known interacting galaxies. These are the prototypicalultraluminous IR galaxy Arp 220, and NGC 6240, which are classifiedas major mergers resulting from a collision of two disk galaxies ofapproximately equal mass, and the prime example of collisional ringgalaxies, the Cartwheel. Our observations provide a new powerful tooland shed some more light to the properties of the hot dust and starformation in interacting galaxies.     

Timing of left-lateral shearing along the Ailao Shan-Red River shear zone: constraints from zircon U–Pb ages from granitic rocks in the shear zone along the Ailao Shan Range, Western Yunnan, China

As the boundary between the Indochina and the South China blocks, the Ailao Shan-Red River (ASRR) shear zone underwent a sinistral strike-slip shearing which is characterized by ductile deformation structures along the Ailao Shan range. The timing issue of left-lateral shearing along the ASRR shear zone is of first-order importance in constraining the nature and regional significance of the shear zone. It has been, therefore, focused on by many previous studies, but debates still exist on the age of initiation and termination of shearing along the shear zone. In this paper, we dated 5 samples of granitic plutons (dykes) along the Ailao Shan shear zone. Zircon U–Pb ages of four sheared or partly sheared granitic rocks give ages of 30.9 ± 0.7, 36.6 ± 0.1, 25.9 ± 1.0 and 27.2 ± 0.2 Ma, respectively. An undeformed granitic dyke intruding mylonitic foliation gives crystallization age of 21.8 ± 1 Ma. The Th/U ratios of zircon grains from these rocks fall into two populations (0.17–1.01 and 0.07–0.08), reflecting magmatic and metamorphic origins of the zircons. Detailed structural and microstructural analysis reveals that the granitic intrusions are ascribed to pre-, syn- and post-shearing magmatisms. The zircon U–Pb ages of these granites provide constraints on timing of the initiation (later than 31 Ma from pre-shearing granitic plutons, but earlier than 27 Ma from syn-shearing granitic dykes) and termination (ca. 21 Ma from the post-shearing granitic dykes) of strong ductile left-lateral shearing, which is consistent with previous results on the Diancang Shan and Day Nui Con Voi massifs in the literature. We also conclude that the left-lateral shearing along the ASRR shear zone is the result of southeastward extrusion of the Indochina block during the Indian–Eurasian plate collision. Furthermore, the left-lateral shearing was accompanied by the ridge jump, postdating the opening, of the South China Sea.     

Canal-side highway in Ho Chi Minh City (HCMC), Vietnam – Issues of urban cultural conservation and tourism development

Since the city’s founding back in 1698 on the old Khmer city of Prei Nokor, rivers and canals have always been Ho Chi Minh City’s (HCMC’s) primary means of transportation. Despite the decline of the utilization of the city’s abundant waterways due to the increasing development of modern aerial services and more convenient roads, the HCMC’s canal-based urban form, with its water-based socio-economic structures that include port-boat-market activities and canal handcraft villages, still processes a rich cultural and religious diversity that dates back to the history of the city itself. Currently, developments in the city’s transportation systems are having a damaging impact on the canals’ cultural background. Rather than being recognized as a significant cultural asset that identifies the city, the canal system has been physically reorganized as the city’s drainage system and valued as only a supplementary landscape element; canal communities have been evicted, and canal built fabric has been removed due to recent canal-side transportation developments. To revitalize the urban cultural identity that is possessed by the canal system and to enrich it as a contemporary valuable layer in the city’s dynamic regional development, it is critical to implement cultural conservation and tourism in the development of canal-side transportation and supplementary projects in the canal vicinity.     

Bioaccumulation of Heavy Metals in Soft Tissues of Bivalve Mollusks from Natural Lakes in Eastern Sikhote Alin (Russia) and the Mekong Delta (Vietnam)

Doklady Earth Sciences - The concentrations of seven heavy metals (HMs) in tissues of bivalve mollusks of the families Unionidae (genera Ensidens, Scabies, Kunashiria) and Cyrenidae (genus...     

Sediment transport trends and cross-sectional stability of a lagoonal tidal inlet on the Central Coast of Vietnam

Lagoonal tidal inlets are a typical morphology of the Central Coast of Vietnam. Recently, navigation channels in these inlets have become increasingly threatened by siltation. This study analyses the relations between sediment distribution and transport trends (using the technique of Sediment Trend Analysis-STA■) in the lagoonal system of the De Gi inlet and then proposes appropriate countermeasures against sand deposition in the navigation channel. The STA identified three types of transport trends in the De Gi inlet, namely dynamic equilibrium, net accretion, and net erosion. Processes associated with the tidal prism have resulted in trends of sediment transport and deposition across the flood and ebb tidal shoals, which maintain a present cross-sectional area of about 1000m^2. However, longshore sediment transport from north to south resulting from northeast waves cause additional sand deposition in the channel. In addition, the effects of refraction associated with a nearby headland and jetty also increase sedimentation. These processes provide the main reasons for sediment deposition in the De Gi inlet. Short term and regular dredging helps to maintain the navigation channel. A system comprised of three jetties (north, south, and weir) is necessary to ensure the longterm cross-sectional stability of the navigation channel.     

Simultaneous Organic Matter and Nitrogen Removal from Piggery Slaughterhouse Wastewater Using Bioaugmented Gaslift Membrane Bioreactor

A single bioaugmentation reactor and a side-stream gaslift membrane bioreactor combined with bioaugmentation are conducted to treat real wastewater from a centralized piggery slaughterhouse in Vietnam. The bioaugmented reactor is inoculated with heterotrophic microorganisms (Bacillus sp.) isolated from piggery slaughterhouse wastewater. The results of a single bioaugmentation experiment show high removal efficiency of chemical oxygen demand (COD) (84.8%–97.5%) and total nitrogen (TN) (69.9%–87.2%) at loading rates of 1.28–3.89 and 0.14–0.37 kg m⁻³ d⁻¹, respectively. The combined system demonstrates a significantly higher TN removal efficiency (89.0%–96.1%) (p < 0.001), more stable flux (36.0–38.4 L m⁻² h⁻¹), and transmembrane pressure (0.95–1.05 bar), and better capacity of separation of solid–liquid phases compared to the single bioaugmentation. High COD and TN removal efficiency is possibly due to assimilation and simultaneous nitrification and denitrification processes. The results of this study also indicate the feasibility and propitious efficiency of the bioaugmented gaslift membrane bioreactor for piggery slaughterhouse wastewater treatment.     

Continental Scale Hydrostratigraphy: Comparing Geologically Informed Data Products to Analytical Solutions

This study synthesizes two different methods for estimating hydraulic conductivity (K) at large scales. We derive analytical approaches that estimate K and apply them to the contiguous United States. We then compare these analytical approaches to three-dimensional, national gridded K data products and three transmissivity (T) data products developed from publicly available sources. We evaluate these data products using multiple approaches: comparing their statistics qualitatively and quantitatively and with hydrologic model simulations. Some of these datasets were used as inputs for an integrated hydrologic model of the Upper Colorado River Basin and the comparison of the results with observations was used to further evaluate the K data products. Simulated average daily streamflow was compared to daily flow data from 10 USGS stream gages in the domain, and annually averaged simulated groundwater depths are compared to observations from nearly 2000 monitoring wells. We find streamflow predictions from analytically informed simulations to be similar in relative bias and Spearman's rho to the geologically informed simulations. R-squared values for groundwater depth predictions are close between the best performing analytically and geologically informed simulations at 0.68 and 0.70 respectively, with RMSE values under 10 m. We also show that the analytical approach derived by this study produces estimates of K that are similar in spatial distribution, standard deviation, mean value, and modeling performance to geologically-informed estimates. The results of this work are used to inform a follow-on study that tests additional data-driven approaches in multiple basins within the contiguous United States.     

Schwermetallbestimmung in Klärwerksschlämmen mittels Röntgenfluoreszenzanalyse

The X-ray fluorescence analysis is an important means for the determination of the heavy metal concentrations in sewage sludges and for the evaluation of their usability in agriculture. Analysis devices from the GDR were used for that. For the investigations there was used as the zero sample a sludge which was not loaded with heavy metals, homogeneous and constantly dried at 105 °C. The drying bed sludge samples were treated with different heavy metal solutions with different concentrations. Preparation of samples, measuring conditions and general spectra are described. The measuring results of tests up to 100 g heavy metal in 1 kg dry substance are critically evaluated. The analysis of a sewer sludge sample takes only about ten minutes. There are determined: Cr, Ni, Cu, Zn, Mo, Cd, Hg and Pb.