A CFD Model to Evaluate Near-Surface Oil Spill from a Broken Loading Pipe in Shallow Coastal Waters

Oil spills continue to generate various issues and concerns regarding their effect and behavior in the marine environment,owing to the related potential for detrimental environmental,economic and social implications.It is essential to have a solid understanding of the ways in which oil interacts with the water and the coastal ecosystems that are located nearby.This study proposes a simplified model for predicting the plume-like transport behavior of heavy Bunker C fuel oil discharging downward from an acutely-angled broken pipeline located on the water surface.The results show that the spill overall profile is articulated in three major flow areas.The first,is the source field,i.e.,a region near the origin of the initial jet,followed by the intermediate or transport field,namely,the region where the jet oil flow transitions into an underwater oil plume flow and starts to move horizontally,and finally,the far-field,where the oil re-surface and spreads onto the shore at a significant distance from the spill site.The behavior of the oil in the intermediate field is investigated using a simplified injection-type oil spill model capable of mimicking the undersea trapping and lateral migration of an oil plume originating from a negatively buoyant jet spill.A rectangular domain with proper boundary conditions is used to implement the model.The Projection approach is used to discretize a modified version of the Navier-Stokes equations in two dimensions.A benchmark fluid flow issue is used to verify the model and the results indicate a reasonable relationship between specific gravity and depth as well as agreement with the aerial data and a vertical temperature profile plot.

Estimation and mapping of water erosion and soil loss:Application of Gavrilovic erosion potential model(EPM)using GIS and remote sensing in the Assif el mal Watershed,Western high Atlas

Water erosion is a serious problem that leads to soil degradation,loss,and the destruction of structures.Assessing the risk of erosion and determining the affected areas has become crucial in order to understand the main factors influencing its evolution and to minimize its impacts.This study focuses on evaluating the risk of erosion in the Assif el mal watershed,which is located in the High Atlas Mountains.The Erosion Potential Model(EPM)is used to estimate soil losses depending on various parameters such as lithology,hydrology,topography,and morphometry.Geographic information systems and remote sensing techniques are employed to map areas with high erosive potential and their relationship with the distribution of factors involved.Different digital elevation models are also used in this study to highlight the impact of data quality on the accuracy of the results.The findings reveal that approximately 59%of the total area in the Assif el mal basin has low to very low potential for soil losses,while 22%is moderately affected and 19.9%is at high to very high risk.It is therefore crucial to implement soil conservation measures to mitigate and prevent erosion risks.

Facilitated Prediction of Micropollutant Degradation via UV-AOPs in Various Waters by Combining Model Simulation and Portable Measurement

The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water matrix.Various reactive radicals(RRs)formed in UV-AOPs have different reaction selectivities toward water matrices and degradation efficiencies for target micropollutants.Hence,process selection and optimization are crucial.This study developed a facilitated prediction method for the photon fluence-based rate constant for micropollutant degradation(K′_(p,MP))in various UV-AOPs by combining model simulation with portable measurement.Portable methods for measuring the scavenging capacities of the principal RRs(RRSCs)involved in UV-AOPs(i.e.,HO^(·),SO_(4)^(·-),and Cl^(·))using a mini-fluidic photoreaction system were proposed.The simulation models consisted of photochemical,quantitative structure–activity relationship,and radical concentration steady-state approximation models.The RRSCs were determined in eight test waters,and a higher RRSC was found to be associated with a more complex water matrix.Then,by taking sulfamethazine,caffeine,and carbamazepine as model micropollutants,the k′_(p,MP) values in various UV-AOPs were predicted and further verified experimentally.A lower k′_(p,MP) was found to be associated with a higher RRSC for a stronger RR competition;for example,k′_(p,MP) values of 130.9 and 332.5 m^(2) einstein^(–1),respectively,were obtained for carbamazepine degradation by UV/H_(2)O_(2) in the raw water(RRSC=9.47×10^(4) s^(-1))and sand-filtered effluent(RRSC=2.87×10^(4) s^(-1))of a drinking water treatment plant.The developed method facilitates process selection and optimization for UV-AOPs,which is essential for increasing the efficiency and cost-effectiveness of water treatment.

Catch organism assemblages along artificial reefs area and adjacent waters in Haizhou Bay

To better understand the community patterns mediated by connectivity in artificial reefs of coastal areas, it is necessary to understand the distribution and coexistence of organisms with artificial reefs area and adjacent waters. This study was conducted to examine main catches assemblages collected by trawls in Haizhou Bay,which included five habitats: the artificial reef area(AR), aquaculture area(AA), natural area(NA), estuary area(EA) and comprehensive effect area(CEA). The result shows that the total abundances of species in the five habitats were highly different(univariate PERMANOVA: P = 0.001, n = 24), but some species were also unique in their habitat(e.g. Scapharca subcrenata and Glossaulax didyma in AA). The body size distribution of specific species between habitats are different. For Collichthys lucidus, their body size in AR(14.63 cm ± 1.64 cm) and EA(14.3 cm ± 0.85 cm) is higher than that in NA(10.65 cm ± 1.64 cm), CEA(11.28 cm ± 1.85 cm) and AA(12.1 cm ±0.43 cm), which indicates the potential connection from AR to EA mediated by their adult population. We concluded that artificial reefs in AR can be considered key components that have the ability to support species assemblages in adjacent habitats. This study has implications for the conservation and monitoring of species assemblages in coastal areas in terms of that artificial reefs can be applied in different stages of habitat protection implementation and in different combinations of scenarios.

Microbiological and Physico-Chemical Analysis of the Waters of the “Mamouwol” Stream in the Urban District of Mamou (Republic of Guinea)

Water is essential to life and to the sustainable socio-economic development of a nation, It is therefore interesting to have a better knowledge of the quality of this water. The aim was to determine the degree of microbiological and physico-chemical pollution of the water of the “Mamouwol” river in the town of Mamou. To do this, we chose four (4) sampling sites spread throughout the town of Mamou. During the month of March (2024), 4 water samples were analyzed to monitor the water quality of this river. The average values of the flora analyzed show that these water are heavily contaminated with bacteria indicative of fecal and metal pollution. This study showed that sites: Mam4;Mam2 and Mam1 contain the highest loads, with Total Coliform counts ranging from 1534 CFU/100 ml to 2100 CFU/100 ml, the number of faecal coliforms varies between 526 and 1240 CFU/100 ml, and that of faecal streptococci between 526 and 841 CFU/100 ml. Metal content, BOD5 and COD all comply with the laboratory’s analysis criteria, although they vary from point to point.

Analysis of the Variability of the Characteristics of Water Resources in the Diani Watershed: Case of the Silissou District

This study aims to analyze the spatio-temporal variability of the characteristics of water resources in the Diani watershed,located in the southeast of the Republic of Guinea.The objective is to assess the availability and quantity of water for sustainable management of this essential resource.The results obtained show a slight variability of hydro-climatic parameters.The most remarkable wet periods by their intensity of(1982-1998)and(2005-2012)are moderate and that of 1986-1990 is extremely severe during which they are felt on all the stations of the South of Guinea.In addition,the dry years,the end of 1970 and 1980 to 1987 recognized by the WMO(World Meteorological Organization)as drought years were highlighted in the Diani watershed in the South of the Republic of Guinea.

Freshening of the Intermediate Waters in the Northern South China Sea over the Past Six Decades

The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the long-term changes in the intermediate water in the SCS have not been thoroughly studied due to limited data,particularly in relation to its thermodynamic variations.This study utilized reanalysis data products to identify a 60-year trend of freshening in the intermediate waters of the northern South China Sea(NSCS),accompanied by an expansion of low-salinity water.The study also constructed salinity budget terms,including advection and entrainment processes,and conducted an analysis of the salinity budget to understand the impacts of external and internal dynamic processes on the freshening trend of the intermediate water in the NSCS.The analysis revealed that the freshening in the northwest Pacific Ocean and the intensification of intrusion through the Luzon Strait at intermediate levels are the primary drivers of the salinity changes in the NSCS.Additionally,a weakened trend in the intensity of vertical entrainment also contributes to the freshening in the NSCS.This study offers new insights into the understanding of regional deep sea changes in response to variations in both thermodynamics and oceanic dynamic processes.

Principles of Technology for Bottling Medicinal Mineral Waters of Sairme Using the Example of Source №3a

Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.

Determination of the Physico-Chemical Quality of the Waters of the Mamouwol River in the Urban Commune of Mamou, Republic of Guinea

Water is one of the most important elements on which our daily lives depend,because of its many uses in various fields.To ensure that people have the right of access to water,the authorities must provide them with treated water that complies with the regulations and standards in force,particularly from a physico-chemical point of view,for all possible uses to avoid any health problems for consumers.The aim of this research is to study the water in the Mamouwol River by measuring physico-chemical parameters:(1)pH,it varies from 5.2“Mam3”to 7.8“Mam4”in August 2021 then from 5.5“Mam3”to 7.7“Mam4”in March 2022,i.e.an average of 6.9 for all sampling points;(2)Turbidity varies from 0.3 NTU“Mam1”to 26.3 NTU“Mam4”in August 2021,then from 0.3 NTU“Mam1”to 30.6 NTU“Mam4”in March 2022,i.e.an average of 9.0 NTU for all sampling points;(3)Suspended matter,varying from 0.6 mg/L“Mam1”to 17.6 mg/L“Mam4”in August 2021,then from 0.6 mg/L“Mam1”to 30.0 mg/L“Mam4”in March 2022,i.e.an average of 8.8 mg/L for all the sampling points“Mam1”,“Mam2”,“Mam3”and“Mam4”;(4)Dissolved oxygen,varying from 2.07 mg/L“Mam3”to 6.12 mg/L“Mam1”in August 2021,then from 1.05 mg/L“Mam3”to 5.05 mg/L“Mam1”in March 2022,i.e.an average of 2.77 mg/L for all sampling points;(5)Nitrates vary from 1.32 mg/L“Mam1”to 3.96 mg/L“Mam4”in August 2021,then from 1.49 mg/L“Mam1”to 5.27 mg/L“Mam3”in March 2022,i.e.an average of 5.53 mg/L for all sampling points;(6)Nitrites,varying from 0 mg/L“Mam1”and“Mam2”to 0.06 mg/L“Mam3”in August 2021,then from 0 mg/L“Mam1”and“Mam2”to 0.13 mg/L“Mam3”in March 2022,i.e.an average of 0.03 mg/L for all sampling points.The results show the presence of organic pollution.

Comparative Study of the Physicochemical Quality of the Waters of the Méné River (Sassandra Watershed, Ivory Coast) in the Dry Season and in the Rainy Season

The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from the river during a period of dry season (January-February) and a period of rainy season (June and September). The various physicochemical parameters were measured according to Afnor standardized methods. The readings of temperature, turbidity, pH and conductivity made it possible to account for the disturbances occurring in water quality. A temporal variation correlated with the seasons (dry or rainy) is noted. Turbidity depends on the concentration of suspended solids (SS) in the water and drained particles and therefore on the seasons. Just like the temperature, the conductivity changes with the season. The waters of the Méné River are generally acidic. The results obtained show that there is a low level of pollution by chlorides, phosphates, nitrites and nitrates. A slight pollution of the waters of Méné in organic matter (chemical oxygen demand values are less than 25 mg∙L−1 during dry season and 32.33 ± 4.73 mg∙L−1 during rainy season) was observed. The concentrations of metallic trace elements such as iron, manganese and aluminum indicate significant pollution of these waters by these elements. Overall, the waters of the Méné River are of satisfactory quality because all the physicochemical parameters analyzed have values below standards during the dry season as well as during the rainy season with the exception of COD and a few metallic trace elements.

An Optimal Algorithm for the Retrieval of Chlorophyll,Suspended Sediments and Gelbstoff of Case Ⅱ Waters in the Pearl River Estuary

An optimal algorithm for the retrieval of chlorophyll, suspended sediments and gelbstoff of case Ⅱ waters in the Pearl River estuary was established with the optical parameters derived from the in-situ data obtained in Jan. 2003 in the same area. And then, the chlorophyll, suspended sediments and gelbstoff of the SeaWiFS pixels on Jan. 29, 2003 corresponding to the in-situ sites of Jan. 25 and 26, 2003 were synchronously retrieved, with average relative errors of 14.9%, 12.1% and 13.6% for chlorophyll, suspended sediments and gelbstoff, respectively. The research results indicated that the optimal retrieval algorithm established here was relatively fit for the retrieval of the chlorophyll, suspended sediments and gelbstoff of case Ⅱ waters in the Pearl River estuary, and had quite good retrieval accuracy.

改良Waters腹膜外剖宫产术

改良Ｗａｔｅｒｓ腹膜外剖宫产术邱学华，杨梦庚，曹光玉，张晓莉，黄飞，尹国武（唐都医院妇产科西安７１００３８）关键词腹膜外剖宫产；新生儿；产后出血中图号Ｒ７１４．２以往腹膜外剖宫产术常存在娩胎困难及手术时间较长等缺点．自１９９２年１２月起，我们以Ｗａｔ...

Agricultural Contamination of the Surface Waters of the Upper Ouémé in Benin: The Case of Heavy Metals and Pesticides

Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10-4 mg/L;2.2 × 10-1 mg/L;1.2 × 10-4 mg/L;2 × 10-4 mg/L), Cadmium (4.4 × 10-5 mg/L;1.1 × 10-2 mg/L;10-4 mg/L;4 × 10-4 mg/L). Then Copper (7 × 10-4 mg/L;3 × 10-3 mg/L;7 × 10-4 mg/L;1 × 10-4 mg/L), Iron (1.51 mg/L;6.4 × 10-1 mg/L;2.0012 mg/L;2.9 × 10-1 mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10-3 mg/L;1.5 × 10-3 mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination.

Waters HPLC检测蔬菜、水果中7种农药残留方法优化

参考现有方法,依据实验室条件,使用Waters2695 HPLC配2998 PDA检测器,检测蔬菜水果中吡虫啉、啶虫脒、多菌灵、除虫脲、灭幼脲、辛硫磷、阿维菌素7种农药残留。通过优化得到良好的分离效果,控制在30min内完成。外标定量分析时,标准曲线R2值在0.9996~0.9999,回收率在87.9%~105.1%,灵敏度和精密度满足分析要求。

Development and evaluation of a DNA microarray assay for the simultaneous detection of nine harmful algal species in ship ballast and seaport waters

Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously,namely A lexandrium tamarense,Gyrodinium instriatum,Heterosigma akashiwo,Karenia mikimotoi,Prorocentrum donghaiense,Prorocentrum minimum,Ulva compressa,Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection(LOD) of 0.5 ng of genomic DNA(orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether,230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%,respectively,relative to conventional morphological methods. This indicated that this high-throughput,automatic,and specific method is well suited for the detection of algae in water samples.

A hydrochemical study of the Hammam Righa geothermal waters in north-central Algeria

This study focuses on the hydrochemical characteristics of 47 water samples collected from thermal and cold springs that emerge from the Hammam Righa geothermal field, located in north-central Algeria. The aquifer that feeds these springs is mainly situated in the deeply fractured Jurassic limestone and dolomite of the Zaccar Mount. Measured discharge temperatures of the cold waters range from 16.0 to 26.5 ℃ and the hot waters from 32.1 to 68.2 ℃. All waters exhibited a near-neutral pH of 6.0-7.6. The thermal waters had a high total dis- solved solids （TDS） content of up to 2527 mg/l, while the TDS for cold waters was 659.0-852.0 mg/l. Chemical analyses suggest that two main types of water exist： hot waters in the upflow area of the Ca-Na-SO4 type （Ham- mam Righa） and cold waters in the recharge zone of the Ca-Na-HCO3 type （Zaccar Mount）. Reservoir tempera- tures were estimated using silica geothermometers and fluid/mineral equilibria at 78, 92, and 95℃ for HR4, HR2, and HRI, respectively. Stable isotopic analyses of the δ18O and δD composition of the waters suggest that the thermal waters of Hammam Righa are of meteoric origin. We conclude that meteoric recharge infiltrates through the fractured dolomitic limestones of the Zaccar Mount and is conductively heated at a depth of 2.1-2.2 km. The hotwaters then interact at depth with Triassic evaporites located in the hydrothermal conduit （fault）, giving rise to the Ca-Na-SO4 water type. As they ascend to the surface, the thermal waters mix with shallower Mg-rich ground- water, resulting in waters that plot in the immature water field in the Na-K-Mg diagram. The mixing trend between cold groundwaters from the recharge zone area （Zaccar Mount） and hot waters in the upflow area （Hammam Righa） is apparent via a chloride-enthalpy diagram that shows a mixing ratio of 22.6 〈 R 〈 29.2 %. We summa- rize these results with a geothermal conceptual model of the Hammam Righa geothermal field.

Construction of Cultural Landscapes in Changjiang Waters of Jingdezhen since the Song Dynasty

Waters of Changjiang River were first defined.As the mother river of Jingdezhen,Changjiang River once was the only way for this ancient ceramic city communicating with the outer world,and played an important role in the economic development and ceramic industry of Jingdezhen.By consulting documents and investigating the local area,this study expounded and proved kiln landscapes of this ceramic city along the Changjiang River,traffic landscapes in the Changjiang River,folk customs and architectural landscapes,as well as unique images.The construction and evolution of its cultural landscapes were analyzed to explore the development history of this city.Characteristic cultural landscapes with the Changjiang River as the principal line were highlighted,"water elements" in the urban development of Jingdezhen,production and transportation of ceramic industry were demonstrated,so as to provide useful references for the reformation project of "one river and both banks",and the construction of new cultural landscapes in Jingdezhen,help Jingdezhen go smoothly in its urban development and transition from a traditional to a modern city.

On the Design Models of Urban Waterscape

Water is an intelligential element in landscape.Taking the planning and design of waterscape in Zixinyuan residential area as an example,the design model and its feasibility are discussed in terms of the design of waterscape and management system of water in urban residential area.It is considered that a good waterscape should satisfy two aspects:firstly,it should display a fine visual effect and profound artistic conception;secondly,the problems such as self-cleaning,recycling,and reuse of water should be solved by the management system to save water resource.The combination of the two aspects can inspire the ecological function of waterscape.And the waterscape and urban cultural environment can be in a harmonious coexistence.

关于美国WaterSence~水箱式坐便器拍盖替换测试的研究

对《WaterSense水箱式坐便器要求》新标准做了简单的介绍,并有针对性地对出口北美市场的WaterSence水箱式坐便器认证产品中较容易出现不符合项的排水阀拍盖替换试验进行了研究和分析。

Geochemistry of Thermal Waters of Continental Margin of Far East of Russia

Studied waters belong to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg/l） Na-HCO3 or Na-SO4-HCO3 thermal waters with high content of SiO2 （up to 81 mg/1） and F （up to 3.9 mg/l）, occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding of water-rock interaction occurring in the water source region. Meteoric origin of waters is proved by stable isotope values varying from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectively. REE patterns reflect high pH, resultfing from water-rock interaction and oxidative conditions. Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1℃ and 82.2-125.8℃ respectively. Presence of deep faults both with abnormal thermal gradient （-45- 50 K/km） define unique geochemical shape of thermal waters of Sikhote-Alin, area, where no present volcanic activity is registered.