bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluctuating hydrodynamics of dilute electrolyte solutions: systematic perturbation calculation of effective transport coefficients governing large-scale dynamics
Authors: Okamoto Ryuichi
Published: September 2022

We study the transport properties of dilute electrolyte solutions on the basis of the fluctuating hydrodynamic equation, which is a set of nonlinear Langevin equations for the ion densities and flow velocity. The nonlinearity of the Langevin equations generally leads to effective kinetic coefficients for the deterministic dynamics of the average ion densities and flow velocity; the effective coefficients generally differ from the counterparts in the Langevin equations and are frequency-dependent. Using the path-integral formalism involving auxiliary fields, we perform systematic perturbation calculations of the effective kinetic coefficients for ion diffusion, shear viscosity, and electrical conductivity, which govern the dynamics on the large length scales. As novel contributions, we study the frequency dependence of the viscosity and conductivity in the one-loop approximation. Regarding the conductivity at finite frequencies, we derive the so-called electrophoretic part in addition to the relaxation part, where the latter has originally been obtained by Debye and Falkenhagen; it is predicted that the combination of these two parts gives rise to the frequency ω
max proportional to the salt density, at which the real part of the conductivity exhibits a maximum. The zero-frequency limits of the conductivity and shear viscosity coincide with the classical limiting laws for dilute solutions, derived in different means by Debye, Falkenhagen, and Onsager. As for the effective kinetic coefficients for slow ion diffusions in large length scales, our straightforward calculation yields the cross kinetic coefficient between cations and anions. Further, we discuss the possibility of extending the present study to more concentrated solutions.
Magnetic field measurement system in vertical status for superconducting undulator cooled in Dewar
Authors: Chen Zilin , He Ping , Li Yuhui , Yang Xiangchen , Wei Junhao , Zhang Xiangzhen , Bian Xiaojuan
Published: September 2022

Superconducting undulators (SCUs) for advanced light sources are being developed rapidly to emit light with higher brightness and flux. The SCU consists of two superconducting magnets with a small gap, each with alternating poles. The SCU is invisible when operating in a Dewar or cryostat, so measuring the magnetic field in the narrow magnetic gap is a challenge in the development of the SCU. This paper presents a measurement system in vertical status for scanning the magnetic field of the SCU along the z-axis. The SCU is immersed vertically in 4.2 K liquid helium in a Dewar and the scanning is powered by a servo motor at room temperature. The measurement system overcomes the temperature difference of 300 K to drive the Hall probes to scan the magnetic field in the narrow magnetic gap of the SCU. In order to make the scanning area of the Hall probes coincide with the trajectory of the electron beam, a lot of detailed work on mechanical aspects has been done, such as controlling the positional accuracy of the Hall probes as they move, high precision machining and limiting the direction of movement. Unlike the currently reported magnetic field scans in the vertical status which are only available for SCU mock-ups of few periods, this system supports magnetic field measurements for SCUs up to 1.5 m long. The measurement system was validated on a 20-period SCU prototype, and after modification, the magnetic field of a liquid helium-cooled 30.5-period SCU was scanned. When the excitation current of the SCU with a magnetic gap of 7 mm is 450 A, the system measured a field distribution with a peak magnetic field of 1 T. The measurement system completed a full stroke trial run of 1750 mm before the 1.5 m SCU was machined. The results of magnetic field measurement from scanning in vertical status can be used as a reference for local shimming and correction of the magnetic poles of the SCU. This work establishes the SCU's ability to operate in cryostat horizontally.
A new theoretical engagement framework for citizen science projects: using a multi-temporal approach to address long-term public engagement challenges
Authors: Liñán Sonia , Salvador Xavier , Álvarez Ana , Comaposada Andrea , Sanchez Laura , Aparicio Nuria , Rodero Ivan , Piera Jaume
Published: September 2022

Effective citizen engagement is generally accepted as one of the most important steps for the success of citizen science programs. However, there is a lack of a common theoretical framework for recruitment and most projects rely on intuition or trial-and-error to develop their engagement strategies. Effective citizen science engagement needs theoretical participation frameworks and the concurrent action of different engagement roles to implement the framework. Besides, we must consider the various short-term and long-term engagement needs of the communities involved in the project. Furthermore, citizen science platforms are evolving towards infrastructures with technical but also social components to ensure long-term engagement. In this study, we have developed and tested an engagement framework for environmental citizen science projects using a novel approach that combines strategies and theoretical models that have proven efficient in other disciplines, such as human behaviour change and persuasion. Our framework is based on four interconnected pillars that feed each other: theoretical engagement models for behavioural change; social design for citizen science platforms; strategies for maintaining volunteer motivation; and strategies to increment the volunteers’ ability. The combination of these four pillars results in a framework that integrates both short-term and long-term interaction mechanisms. This multi-temporal approach ensures keeping volunteers motivated and engaged for long periods, a requirement for many citizen science-monitoring programs. In addition, the theoretical framework points out the benefits of considering citizen science projects as a collaboration between multiple stakeholders to ensure long-term engagement. These stakeholders include the volunteers, but also new roles such as enabling communities that act as a bridge between volunteers and academia. Specifically, we have successfully tested this framework in a marine citizen science case study that monitors urban beaches. Furthermore, together with the proposed framework, we provide specific guidelines to help managers to design tailored strategies for their citizen science projects.
Pesticide contamination of freshwater ecosystems: mapping vulnerable areas and mitigation scenarios in the Prosecco DOCG wine production area
Authors: Pappalardo Salvatore Eugenio , Ferrarese Francesco , Pizarro Patricia Mariot , Loddo Donato , De Marchi Massimo
Published: September 2022

Freshwater ecosystems are the most vulnerable environments worldwide and the most biodiverse, providing essential ecosystem services. The role of land management in agriculture is paramount with the dramatic increase in pesticides: two million tonnes used worldwide (47.5% herbicides, 29.5% insecticides, and 17.5% fungicides) are jeopardising freshwater ecosystems. Concerns about the risk of pesticide contamination from viticulture have led to implementing nature-based mitigation measures (buffer strips and hedgerows) and technical improvements. The general aim is to assess spatial proximity among vineyards and river networks within the Prosecco denominazione di origine controllata (DOCG) area to identify potential critical areas for pesticide contamination. Specific objectives are: (a) mapping vineyards within the Prosecco DOCG area, (b) identifying river banks with a higher probability of experiencing pesticide contamination, and (c) mapping critical areas potentially affected by pesticide contamination. Spatial modelling was based on very high geometric resolution ortophotos (0.5 m), laser imaging, detection, and ranging (LiDAR) data (1 m), and morpho-hydrological parameters of the river network. Proximity and morpho-hydrological modelling showed that due to little distance from Prosecco croplands (5–20 m), freshwater ecosystems may be affected in different basins by spray drift pesticide contamination. Distances between vineyards and streams were shown to be critical, as 35.7% and 13.9% of river banks were within 20 m and 5 m distance from vineyards, respectively. Furthermore, 52% of basins presented river banks intersecting vineyards at 5 m, while 37% were within 20 m distance. Such hotspots should be investigated in the field for watershed-based quality assessment. However, mitigation scenarios indicate that spray drift contamination might be reduced by 75%, minimising the effect from 20 m to 5 m distance from vineyards and, therefore, avoiding reaching part of riparian and aquatic ecosystems. Geovisualisation of river banks proximity at watershed level offered insight into area with high probability of experiencing pesticide contamination from vineyards due to spray drift.
Pectinase Activities of Selected Fungi Grown on Agrowastes via Solid-state Fermentation
Authors: Ametefe G. D. , Lemo A. O. , Orji F. A. , Lawal A. K. , Iweala E. E. J. , Chinedu S. N.
Published: September 2022

Pectinases accelerate the breakdown of the glycosidic bonds in pectin into simpler forms. Pectinases in the study were produced using three extraction solvents, three fungi, and six substrates. Citrate buffer, distilled water and 0.1 M NaCl were utilized as extraction solvents. Penicillium sp, Pichia kudriavzevii F2-T429-5 and Aspergillus niger were selectively isolated from the environment and identified. The substrates include; wheat bran, banana peels, orange peels, corn cobs, Thaumatococcus daniellii (sweet prayer plant) fruit peels, and leaves in solid-state fermentation. The dinitro salicylic acid (DNS) technique was used to determine pectinase activity. In comparison to distilled water, the study found that extracting the enzyme from the fermentation medium with 0.1 M NaCl solvent resulted in considerable (p<0.05) activity. The best substrate and fungus were orange peels and Aspergillus niger, respectively. In general, when compared to the yeast Pichia kudriavzevii F2-T429-5, the molds (Penicillium sp. and Aspergillus niger) produced pectinases with higher activity. Orange peel resulted in pectinase production with significant (p<0.05) activity compared to wheat bran, banana peels, corn cobs, Thaumatococcus daniellii (sweet prayer plant) fruit peels, and leaves. Additionally, Pichia kudriavzevii F2-T429-5 in Thaumatococcus daniellii fruit peel fermentation produced pectinase with the lowest activity. The inference drawn from the study shows the potential of T. daniellii fruit peels, its leaves, and Pichia kudriavzevii F2-T429-5 for pectinase production.
Hygiene Assessment of Paper Currency and Fomites Handled by Food Vendors in Covenant University
Authors: Nwinyi Obinna C. , Chukwukadibia Somachi Q. , Kayode-Afolayan Olushola D.
Published: September 2022

Fomites have been known to harbor significant amount of microbial load and its handling by food vendors poses a significant risk to consumers. In this study, swab samples were collected from vendors handling paper currency; their food contaminated hands, and selected foods-Akara, Suya and Bole. These fomites were evaluated for organisms that may pose a risk of food infection/contamination. The organisms isolated were identified based on their macroscopic, mi-croscopic and biochemical characteristics and comparison with standard reference organisms. From the results obtained, the paper currency had the highest numbers of bacterial and fungal load (too numerous to count – TNTC), food contaminated hands ranged between 12 x 105- 15 x105 cfu/g and the selected foods- Akara, Suya and Bole had 7x105- 12 x105 cfu/g. The bacteria members’ species recorded include Pseudomonas, Streptococcus pyogenes, Shigella, Proteus vulgaris, Escherichia coli, klebsiella pneumonia, Salmonella typhi, Enterobacter sp, Aeromonas hydrophila, Micrococcus luteus. Others include Clostridium sp, Staphylococcus aureus, Staphylococcus epidermidis and Bacillus cereus. The fungal species reported include Aspergillus, Yeast, Penicillium sp. and Saccharomyces spp. Mucor sp. and Rhizopus sp. Members of Staphylococcus aureus and Escherichia coli were noted to occur on all the samples surveyed. From this study, it can be deduced that handling of paper currencies by food vendors could serve as a direct and indirect pathway for man-microbe interface.
Genetic Diversity, Conservation and Improvement of Gongronema latifolium Benth., in South-Eastern Nigeria Using the Internal Transcribed Spacer – ITS
Authors: Conrad Omonhinmin A. , Chinedu Onuselogu C.
Published: September 2022

Gongronema latifolium Benth., is listed among the important vegetable with medicinal attributes. Its native habitat currently threatened in Nigeria and there is death of molecular genetic information important for breeding and conservation purposes. To study the species genetic diversity, 50 accessions were collected from South Eastern Nigeria where the species is endemic and was subjected to molecular evaluation using the non-coding internal transcribed spacer (ITS 4 and 5) location. Relatively high within population gene diversity and low nucleotide (base) diversity was identified among the fifty (50) accessions. AMOVA analysis highlighted 93% within population diversity (variations). FST = 0.074 genetic differentiation was recorded for genetic diversity. Principle component analysis (PCA) segregated the accessions into four large groups (A-D), along non-geographical lines; with four outliers’ accessions; AwkCH051 (Akwa Ibom), EnuCH014 (Enugu), EboCH036 and EboCH037 (Ebonyi). Expectedly, the species recorded low-moderate genetic diversity common for organisms experiencing decreasing cover range. Enugu recorded the least within population diversity and Ebonyi showed higher diversity than states and might constitute the core of a possible genetic centre for the species. The outlier accessions represent potential parental lines for breeding and improvement programmes. Conservation efforts comprising in situ and ex situ strategies are required to arrest the declining diversity of the species in its native range across Southern Nigeria. Conservation and improvement efforts will sustain the uses of the plants, reduce poverty and improve the livelihood of gatherers, farmers and vendors of the plant, who are particularly women in the region.
Estimation of Residents Exposure Risks to Radiological Parameters in Some Building Materials in Nigeria
Authors: Adewoyin Olusegun O. , Omeje Maxwell , Akinwumi S. A. , Zaidi Embong , Ogundiran Funso A.
Published: September 2022

Some of the brands of tiles commonly available in the markets in Nigeria, which are used for building purposes, were analysed in order to estimate the concentration of naturally occurring radionuclides. The analysis was done with the aid of High-Purity Germanium (HPGe) detector. The results revealed that the average activity concentrations in the sample of tiles, cement and sand varied from 41 ± 4 to 96 ± 8.3, 27 ± 9.5 to 76.5 ± 2.5 and 140 ± 7.9 to 940 ± 19.2 Bqkg−1 for 232Th, 226Ra and 40K, respectively. The results obtained were used to determine the impact of these building materials on users. The radium equivalent activity (Raeq) ranged between 125 – 280 Bqkg−1 and were observed to be lower than 370 Bqkg−1 in all the samples tested, which is the recommended safe limit. Similarly, the absorbed dose rates were noted to vary from 51.00 – 122.52 nGyh−1. However, one of the samples examined showed a result of 122.52 nGyh− for the indoor absorbed dose rate (DR), which is higher than the internationally recommended safe value of 80 nGyh−1according to USEPA. The results revealed that the building materials investigated do not pose any danger to the end users.
Contemporary Shelter in the Built Environment: A Comparative Review of Social Housing Schemes in Selected European and African Nations
Authors: Aduwo Egidario Bridgette , Ejale Eghonghon Anne , Ibem Eziyi Offia
Published: September 2022

Social Housing remains highly essential in providing affordable shelter in urban and peri-urban settlements. However, pressures from liberalisation, public expenditures, and privatisation continue to threaten its availability. This paper reviews contemporary social housing trends and compares Europe’s established social housing scheme to Africa’s emerging schemes. This was achieved by identifying the similarities between social housing in the UK and the Netherlands and social Housing in Nigeria and South Africa and identifying the differences between them. Relevant literature was reviewed to give a detailed but straightforward account of the Netherlands, UK, South Africa, and Nigeria based on allocation policy, target occupants, ownership scheme, mode of finance, and the challenges faced. The studies conclude that there are more similarities between social Housing in Europe and Africa than differences. However, the most fundamental difference is the type of challenges they face. The challenges observed in Europe’s social housing schemes are social problems such as segregation and bad public image. In contrast, Africa’s social housing challenges are socio-economical in terms of lack of funds, poor planning, and implementation of policies. The outcome from this study is targeted at promoting the implementation of sustainable social housing schemes at the policy level.
Investigation of The Impact of Noise Control Strategies in Sustainable Building Design
Authors: Adewale B. A. , Stephanie Mozimo
Published: September 2022

The design of each city inextricably influences the pattern of noise pollution across the globe. Many aspects of urban planning can significantly affect vehicular distribution, traffic conditions, and the volume of traffic. Lagos State, in particular, is afflicted by some of these factors. Numerous studies have established the significance of noise control strategies in this context. This paper focused on precautionary noise control strategies incorporated at the design stage, which are an integral part of a sustainable urban planning approach. Data were collected via a structured questionnaire from a sample consisting of 96 designers and 67 users of mixed-use buildings in Lagos state; as these building types promote sustainability in building design. This research utilized the Statistical Package for the Social Sciences (SPSS) to analyze data. The results reveal which noise control strategies have been adopted and implemented in sustainable building designs and as a result, its users are not affected by external noise sources. The study’s findings had a positive impact on the implementation of sustainable urban planning strategies that incorporate precautionary noise control strategies.
Effects of Wastewater Management on the Environment: A Case Study of Selected Shopping Malls in Ota, Ogun State, Nigeria
Authors: Oyelami B. J. , Sholanke A. B. , Ekhaese O. N. E. , Olusore S. P.
Published: September 2022

The study investigated wastewater management in selected shopping malls in Ota, Ogun State, Nigeria and the effects on the environment, towards identifying areas for possible improvement. The study adopted a qualitative methodology. Data was collected from both primary and secondary sources. Primary fieldwork data were collected using structured observation and interview guide, while secondary data were gathered from both published and unpublished literature by textual analysis. The study discovered that the wastewater management system employed by the shopping malls investigated were mainly on-site wastewater management systems that were not effective as a result of the way they were poorly managed. The shopping malls were found to release greywater into the environment that is leading to environmental degradation of the study environs. The study recommended that relevant government waste management authorities need to do more to ensure that shopping malls and other commercial public facilities, manage their wastes in line with standard best practices, to avoid degrading the environment. The authorities are to check and approve the design of wastewater management systems, as well as conduct routine checks to ascertain that the systems are functioning as expected, towards achieving a better wastewater management effective and sustainable environment.
Architectural Mitigating Strategies for Air Pollution in the Built Environment
Authors: Igwe Ajuluchukwu E. , Ezema Emmanuel C. , Okeke Francis O. , Okpalike Cyriacus
Published: September 2022

Air pollution and air pollutants effect on humans and the atmosphere in general, is now an issue of great concern to researchers globally. Consequently, efficient mitigating strategies need to be introduced for the sake of the environment and most importantly human health. To this effect, this study aims to investigate possible ways through which architecture can help curb air pollution and air pollutants in the atmosphere through innovative architectural design strategies and controlled construction practices, with specific guidelines on how to achieve these strategies. The study in the quest to achieve the above aim employed the literature review research design, with particular reference to works of literature that dwelt on innovative and sustainable design strategies within the built environment. Evidence in literature reveals that air pollution is one of the major issues faced by man due to high level of industrialization and lots of other human activities, with a majority of the research dwelling on how pollutants are being generated but just a few studies dealt on how architectural and construction practices contribute to air pollution and the possible ways to reduce the effect of air pollution and air pollutant to the atmosphere through innovative design strategies, which is where this study plays a major role in filling that gap. The research finding from this study ascertained that all stages of building development projects from the inception of the project to its deconstruction release pollutants into the atmosphere. It concludes that the most effective way of controlling air pollution within the built environment is through the use of greenery (bio facade) and adopting a sustainable design system. The study will help inform government environmental agencies, architects, urban planners, builders, and all other stakeholders in the built environment on sustainable ways to tackle air pollution in the urban areas, most especially where there is no luxury of land for the planting of trees and vegetation.
Spatial Distribution of Gamma Dose Rates in the Marine Environment of Unumherin Community in Niger Delta, South-South, Nigeria
Authors: Aimua Godfrey U. , Omeje Maxwell , Adewoyin Olusegun O. , Usikalu Mojisola R. , Joel Sunday E. , Ekwueme Benjamin N. , Ifeanyi Oha A.
Published: September 2022

This work investigates the radioactivity distribution of coastal polluted areas of Unumherin Community in Niger Delta, Nigeria. The measurement of the outdoor dose rate of the polluted coastlines was carried out using calibrated hand-held gamma detector, (RS-125 Gamma-Spec). The spatial distribution of gamma dose rate indicates the hotspot at location 4 with a value of 100 nGy/h. Maximum and minimum values of the absorbed dose-rate was observed in location 4 with the value of 100 nGyh
−1 and location 15 with the value of 2 nGyh
−1, respectively. This is an indicative that the risk of ionizing radiation exposures is much higher for location 4 than other locations. This higher value of 100 nGyh
−1 is far more than the recommended limit of 59.00 and 84.00 nGyh
−1 provided by UNSCEAR, 2000. The community requires much more radiological monitoring for the safety of human and ecosystem.
Climate Justice and Biodiversity
Authors: Vasiliev Denis
Published: September 2022

Global climate change is affecting both natural environment and human society. National governments engage in climate mitigation actions. Transnational agreements such as Paris Agreement and recent UN Climate change conference (COP 26) intend to foster global collaboration on tackling climate change. However, activities and policies aiming to address the problem may either undermine integrity of the natural environment and human society or can contribute to sustainable development. Here climate justice plays the central role. Pursuing climate justice paradigm, may environmental organizations to prove central role of forest conservation in mitigation of climate change. This is likely to allow avoiding trade-offs between clime, economic development and biodiversity conservation objectives. Multiple real live examples demonstrate the potential of climate justice as a central principle of climate actions to allow finding win-win solutions. The central principle of climate actions and policies should be avoiding harm to biodiversity and indigenous peoples. The approach is likely to ensure sustainable development and success in addressing climate change.
Assessment of Indoor Air Quality in Childbirth from the Point of View of Pregnant Women - Case Study
Authors: Zielinko Paulina , Krawczyk Dorota Anna
Published: September 2022

Indoor air quality (IAQ) should be appropriate in places, where people spend most of their time. This concept is strongly related to the topic of health and comfort of users of an antenatal classes, as indisputably IAQ parameters should be adjust to recommended level, to provide descent conditions for pregnant women. This paper was created to examine the indoor air quality in the rooms, where pregnant women spend most of their time, the paper shows results of research of selected parameters of indoor air quality in the building where antenatal classes are located. The measurements were carried out in Bialystok (Poland). Experimental research data were analyzed in respect of recommendations and compared with results of the survey, carried out among the participants during gymnastic and auditorium classes. For more accurate analysis, the paper presents the simulation of variability of carbon dioxide concentration with different value of air change rates and number of users. Moreover simulations of energy consumption were conducted. The work is summarized with conclusions indirectly related to the quality of the supply-exhaust ventilation system installed in the school, determining the level of its effectiveness and precision.
Hydrogeological Conditions and Mathematical Model of the Area Surrounding Hatra Suggested dam, Northwest Iraq
Authors: Ali Mohammed Abdilfattah , Salih Sabbar Abdullah
Published: September 2022

The area was hydrogeologically studied, it was found that the main aquifer is unconfined, it is located within Fat’ha Formation, and the hydraulic properties of this aquifer were also studied from the analysis of pumping tests data to determine the averages of transimissivity (T=671.027 m2/day), hydraulic conductivity (K=45.449 m/day), and storage coefficient (Sc=0.226). The groundwater levels and flow direction map was drawn, and it was found that the flow corresponds to the topographical slope of the land surface towards Tharthar valley, from the east - west towards the center of the study area, with a slight slope towards the south.

These are some data represent a database that can be used in the design of the proposed dam on Tharthar valley, and the policy of storage and water management in the dam, reservoir as well as to build a mathematical model to predict the future behavior of groundwater in the region.

Especially under the body of the dam to simulate the changes in groundwater conditions in the area of the small Hatra Dam Suggested on Tharthar valley, when storing water in front of a dam, and the expected engineering problems that would occur due to groundwater seepage under or on both sides of the dam body, by raising the water level within the valley – hypothetically, by 1m, 2m, 3m, 4m, 5m, 7m, 9 m and 11 m, assuming no pumping from the Aquifer during the rise of the level in the valley. as well as re-calculation with the same ranges of raising the level on another assumption, which is pumping from the wells in the area by 9 m3/ hour, for a period of time 6 hours per day, and determining the affected area by raising the level for each of the cases. The study indicated that the expected effect on the groundwater level starts when raising the water level inside the valley to four meters, and the clear increase continues at five meters, but the cumulative effect of raising the level from (7-11)m is slight. It also identified the sites that would allow the underground water to be pumped under the dam’s body, and the results were consistent with the geological reality of the area. These results will help in establishing an appropriate design for the foundations and structure of the dam.

The current study is one of the requirements for building a small dam within the plan for managing water resources and developing the region that suffers from desertification, drought and environmental degradation.
Interaction of Rutba-Dhabaa Groundwater with the Mulussa Aquifer Host Rocks, Western Iraq
Authors: Al-Kubaisi Qusai Y. , Al-Kubaisi Mahmood H. D.
Published: September 2022

Mulussa aquifer extended the area of Rutba-Dhabaa, Western Iraq, has been studied in order to determine the most important chemical functions and interaction between rocks and groundwater (Groundwater–rocks interaction). The results of wet and dry periods indicated that Ca2+and SO42- in the groundwater are the dominant ions. Average of Hydrogen Number (pH), Total Dissolved Solids (TDS), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), chlorine (Cl-), sulfate (SO42-), bicarbonate (HCO3-) and nitrate (NO3-) are 7.43, 718.25 mg/l, 120.8 mg/l, 40.875 mg/l, 32.865 mg/l, 2.93 mg/l, 103.527 mg/l, 195.9 mg/l, 214.85 mg/l and 4.275 mg/l respectively in the dry period, while its averages 7.33, 664.2375 mg/l, 114.25 mg/l, 35.8 mg/l, 29.28 mg/l, 2.33 mg/l, 90.3 mg/l, 181.1 mg/l, 203.85 mg/l, and 3.6 mg/l respectively in the wet period. The groundwater is characterized by low alkalinity hard to very hard water, between moderately and excessively mineralized water, and fresh to slightly water in both periods. Rock–water interaction processes are indicating that there is a possible contribution of the seawater in Mulussa aquifer, the dominant process is limestone–dolomite weathering, where the source of calcium is rather than gypsum or silicates rocks, and contribution of calcite more than dolomite in the Mulussa aquifer.
Application of 2D and 3D Electrical Resistivity Imaging Techniques for Site Investigation in Ramadi City, Western Iraq
Authors: Abbas Sameer Sh. , Ahmed Muhanna M. , Abed Ali M. , Al-Menshed Firas H.
Published: September 2022

Ramadi city, western Iraq, is considered an area with risks resulting from the presence of gypsum soil near the surface and the water table on shallow depth which facilitates the solubility of the soil and creates a weak area. So a dipole-dipole array with an n factor of 6 and a -spacing of 2 m was used. Ten 2D resistivity imaging traverses and 3D resistivity imaging station were done. The robust constrained inversion method is used to obtain 2D and 3D models. The results show that the topsoil layer extends to 2m depth with resistivity of 800 to 4000 Ωm. This is caused by high inhomogeneities in the deposits. The weakness zones and Depositional lenses appears after 2m depth and extent to 9m with resistivity value extend from 200 to 800 Ωm. Finally, it is concluded that four main reasons for civil engineering failure in Ramadi city. These reasons may be the inhomogeneity of the underground deposition material. In addition, the existence of weak areas and sedimentation lenses, and the change of water table.
Evaluation of Seepage on the Right Side of Haditha Dam, West of Iraq
Authors: Ibrahim Ameen Mowafaq , Salih Sabbar Abdullah , Irzooki Raad Hoobi
Published: September 2022

The study aims to assess the water seepage through the right side of Haditha dam structures in western Iraq, using the finite elements method by an advanced computer software (SEEP/ W, 2012), the earth fill dam is 9 km long on the Euphrates River. Many attempts were done to ascertain the results of the program on a supposed earth dam and compare the results with the other analytical methods. The comparison reveal to very close results, and this indicate the suitability of the software for Haditha dam structures seepage analysis. After the verification of the results, then the real design information of the dam was input to analyse the dam, the input data are the height of the dam, width, slope of upstream and downstream, dimensions of the core, hydraulic conductivity of the different materials of the dam and the foundations. The results obtained from the SEEP/W2012 software were compared with the actual field data of the seepage amount for years (1989 - 2017) and with the water level in the dam reservoir for different periods. The result of comparison gave an idea to the efficiency of the dam protection against the seepage.

Through the SEEP/ W data, which simulates the dam sections, levels and discharges that calculated by the software, which is compatible with the field monitoring data, it can be said that the software was able to simulate the actual conditions of the dam and identify the weakness zones. Where the results displayed that the asphaltic diaphragm in good condition and efficient on the right side of the dam. The grouting curtain in the right side is efficient, except for the area between the two stations 15 and 25, the zone between two stations need a continuous monitoring. The results also reflect that earth fill materials and the central core of the dam are efficient, and seepage within permissible design values.
Seismicity of Iraqi western desert and surroundings: As an example of continental intraplate seismicity
Authors: Al-Halboosi Jasim M. , Mohammad Osama J. , Al-Heety Emad Abdulrahman
Published: September 2022

Seismicity of Iraqi western desert and surroundings was investigated using a complete and unified magnitude earthquake catalog covering the interval from 1900 to 2017. A marked rise in number of the events in the study area was observed after the year 2000 compared to the previous years. The magnitude of majority of the recorded events ranged from 2 to 3.5 Mw. The value of b-constant in frequency-magnitude relation is 0.7. The epicentral distribution shows that the western desert is aseismic to very low seismicity area compared to the surrounding regions. The epicenters were clustered in five seismogenic zones. The focal depths division of the events exhibits that majority of the earthquakes occur in the upper crust. A causal relation may be between the study area seismicity and the zones of weakness and /or stress condensation at the fault intersections.
Comparison of the Manifestations of Western Region-Iraq Karst and Some Typical Karst Areas in the World
Authors: Al-Hetty Salam O. , Al-Salmani Nazar Z. , Mohammad Osama J.
Published: September 2022

Karst is one of the geological manifestations that form different earth shapes and scenic landscapes. Which are generally divided into surface landscapes that are important its sinkhole and the sub-surface landscapes. The research aims to compare the manifestations of karst for the study area and the typical karst (holocaust) areas in the world. The most important of which are the caves, which result from the process of dissolution the rocks of all kinds, But the most important rocks formed for karst carbon rocks, especially limestone rock, due to its abundant and moderate solubility. add to evaporated rocks, especially gypsum, come second in the form of karst manifestations. There are several surface landscapes karst forms in the Western Desert such as a Solution and Collapse Sinkhole and subsurface landscapes karst such as cavities formed from carbonate and gypsum rocks. Landscapes karst distribution in variable shapes and dimensions on surfaces of the plateaus on Zor Hauran, Ubaid, Hussainiyat, Amij, Dammam, Umm Er Radhuma, Russ, and Ms`ad within Euphrates Fatha and Zahra formations, which belongs to Mesozoic and Cenozoic eras times. The meaning of the non-typical karst is that the surface karst forms such as (Sinkholes) and the subsurface karst forms such as (cavities) are few in number in addition to the size, depth and dimensions of these phenomena are small compared to the typical karst forms, which are characterized by the abundance of their numbers in addition to the huge size of these karst phenomena. There are a number of reasons and observations that make this phenomenon unclear and not typical for the study area because of Lithology, geomorphology, tectonic, and climatic reasons. In addition to the time factor, which has a main role in the development of karst. The type of karst in Iraq belongs to the arid and semi-arid karst group depending on classification of karst assemblages according to climate.
Miocene Stratigraphy of Abu-Jir Fault Zone, Al-Baghdadi Sub-Basin, Western Iraq.
Authors: Al-Qaisi Rasha , Alhadithi Abdulkhalq A. , Al-Hadidy Aboosh
Published: September 2022

Stratigraphy of Late Oligocene to Middle Miocene age, suggested the carbonates evaporate succession in the area between Heet and Haditha cities within Abu-Jir fault zone has distinguished as “Al-Baghdadi sub-basin” after Al-Baghdadi city. It has NW–SE trending align the western bank of the Euphrates. Al-Baghdadi sub-basin is a local basin, which forms a part of the western marginal of the large foreland Tertiary basin (Zagros Basin) that was created on the Arabian shelf as a result of the collide of Arabian and Eurasian plates. The impact of the Abu-Jir fault on the formations on both regions of the Euphrates has been determined by observing the changes in thickness and lithofacies of the Euphrates, Jeribe and Fat’ha formations. On the western side, the Euphrates and Fat’ha formations were deposited with a relatively a little thickness, with absence of the Jeribe Formation between them and the top of the Euphrates Formation is above sea level. On the eastern side of the Euphrates River, the three formations were deposited with large thickness as compared to the western side, and the top of the Euphrates Formation is below sea level. This is enough to indicate that the western side was uplifting locally due to the activity of the Abu-Jir Fault as a positive flower structure during Miocene, while the eastern side was subsiding. Abu-Jir fault zone behaves as the basin bounding fault that acted like a growth fault. There are also variations in lithofacies between outcrops within Al-Baghdadi sub-basin as revealed from lateral missing or thinning of some layers.
Geometric optics analysis of inverted graded index fibers
Authors: Zubia Joseba , Aldabaldetreku Gotzon , Durana Gaizka , Illarramendi María Asunción
Published: September 2022

We derive a general solution based on geometric optics that describes the light propagation properties in multimode optical fibers with inverted refractive index profiles. Using this general solution, we classify rays according to their propagation properties and calculate the analytical expressions of the ray trajectories inside these fibers under different launching conditions. In addition, we discuss the most suitable propagation conditions that maximize the confinement of light power in the vicinity of the core-cladding interface for sensing purposes.
Molecular dynamics analysis of friction-triggering process with spherical probe
Authors: Cheng Rongjun , Chen Jiaxing , Jian Hebang , Huang Qiangxian , Zhang Liansheng , Li Hongli
Published: September 2022

Molecular dynamics simulation with embedded atom method/Finnis–Sinclair potential function was utilised to study the friction properties of the friction-triggering process at the mesoscopic scale. The sliding friction process of a spherical probe with different diameters on the surface of a single-crystal aluminum matrix was simulated and the influences of sliding friction on the atomic behaviour of the surface under different contact conditions were analysed. The relationship between contact force and friction coefficient with spherical diameter was studied. The research shows that the plastic groove, normal force and friction force increase with the increase in probe diameter in the sliding friction process. The contribution of increasing spherical diameter to normal force is greater than that of friction force. The coefficient of friction varies with the ratio of the actual contact area to the normal force. After the running-in process is stable, the friction coefficient fluctuates around a certain value as theoretically verified by the two-term friction law. The increase in the diameter of the spherical probe leads to the increase in the number of dislocation atoms in the workpiece and the formation of dislocation rings, which result in the difference in the sliding friction process under indenters with different diameters. The results provide valuable reference for friction-triggering measurement based on 3D nanometre probes such as friction force microscopy.
Investigation on microstructure and impact toughness of simulated heat affected zone of high strength low alloy steels by laser-arc hybrid welding
Authors: Bao Liangliang , Huang Yiping , Liu Fujian , Xu Yanhong , Ouyang Kai , Han Tao
Published: September 2022

The microstructure and impact toughness of the simulated heat affected zone (HAZ) of a high strength low alloy steels by laser-arc hybrid welding (LAHW) were investigated in this paper. Homogeneous simulated HAZ specimens with different grain sizes were prepared using the welding thermal simulating technique. Instrumented impact test was conducted to investigate the toughness of the simulated HAZ. Multi-scale sub-structure characterization of the simulated HAZ specimens was implemented by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron back-scattered diffraction (EBSD). The instrumented impact test found that the peak temperature T

M
mainly affected the crack propagation process, the crack propagation energy E

p
decreased as the increase of T

M
, while the crack initiation energy E

i
barely changed, the decrease of crack stable energy E

a
led to the change of E

p
. The multi-scale sub-structure characterization showed that the prior austenite grain size (PAGS), packet width, block width both increased with the rise of T

M
. The block width was similar to the facet size in the crack unstable propagation zone of the simulated HAZ specimens. The block was the microstructure unit controlling the crack propagation process of the LAHW simulated HAZ specimens.
Copper-based metal-organic framework for highly efficient adsorption of lead ions from aqueous solution
Authors: Lee Joon Yeob , Choi Jeong-Hak
Published: September 2022

A nanomaterial, a copper-based metal organic framework (Cu-BTC MOF), was prepared by a one-step solvothermal synthesis method and applied for the removal of Pb(II) ions from an aqueous solution via adsorption. The Cu-BTC MOF nanomaterial was characterized via x-ray diffraction, Fourier transform infrared, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive x-ray spectroscopy (EDX), and Brunauer–Emmett–Teller method. TEM and SEM images of the prepared Cu-BTC MOF presented octahedral crystals. Furthermore, EDX spectroscopy showed that the synthesized porous nanomaterial consisted of Cu, O, and C elements. The prepared Cu-BTC MOF was employed as an adsorbent for the removal of Pb(II) ions from an aqueous solution. Adsorption kinetics and adsorption isotherm modeling were conducted in detail. The maximum adsorption capacity values of the Cu-BTC MOF for Pb(II) ions at temperature conditions of 10, 25, and 40 °C were 890.94, 896.04, and 958.37 mg g−1, respectively. The synthesized Cu-BTC MOF showed high distribution coefficient (Kd) values, and it was very effective in extracting Pb(II) ions. In the Pb adsorption process, the molar ratio of Pb adsorption/Cu desorption was found to be close to 1 indicating that ion exchange with Cu ions in the Cu-BTC MOF material occurs and the cation exchange between Pb ions and Cu ions can be considered as a dominant mechanism of the adsorption.
Study on the preparation of silicon carbide from carbon in waste cathodes
Authors: Liao Hui , Li Longjiang , Mao Song
Published: September 2022

Silicon carbide as the core material for third-generation semiconductors plays an important role in many fields; however, its large-scale applications as well as low-cost synthesis remain a challenge. Silicon carbide was prepared via carbothermal reduction using silicon dioxide and purified waste cathodes as the carbon source. The optimum conditions for preparing silicon carbide using waste cathodes are temperature = 1550 °C, molar ratio of carbon to silicon = 3:1 and holding time = 3 h. The microstructure of the prepared silicon carbide was investigated using x-ray diffraction (XRD), infrared spectroscopy and scanning electron microscopy (SEM). The XRD results of the prepared silicon carbide showed that β-SiC was the main phase of the prepared silicon carbide. The SEM results showed that the prepared silicon carbide was fibrous. The growth mechanism of silicon carbide was proposed using the thermodynamic calculations of chemical reactions.
Inconsistent evolvement of micro-structures and corrosion behaviors in cold/warm deformed austenitic stainless steel
Authors: Tao Huimin , Ding Mingming , Shen Cheng , Zhang Lin
Published: September 2022

The effects of cold/warm deformation on the micro-structures and corrosion properties of type 304 stainless steel (SS) were studied by micro-structural analysis and electro-chemical tests. Strain-induced α′ martensite was produced by cold deformation but not by warm deformation at 100 °C, and it significantly influenced the surface nanohardness of SS. The corrosion resistance of the cold deformed 304 SS continued to decrease as the deformation reduction increased, while the corrosion resistance of the warm deformed 304 SS first decreased and then increased. The increases in strain-induced α′ martensite and dislocation tend to promote corrosion, but the increases in low-∑ coincidence site lattice boundaries, low angle grain boundaries and the severely disrupted random grain boundaries tend to resist corrosion. Warm deformation may provide a possibility of obtaining type 304 SS with high-strength and corrosion resistance, which is attributed to the coupling effect of dislocation and grain boundary.
AGP-based unitary coupled cluster theory for quantum computers
Authors: Khamoshi Armin , Chen Guo P , Evangelista Francesco A , Scuseria Gustavo E
Published: September 2022

Electronic structure methods typically benefit from symmetry breaking and restoration, specially in the strong correlation regime. The same goes for ansätze on a quantum computer. We develop a unitary coupled cluster method based on the antisymmetrized geminal power (AGP)—a state formally equivalent to the number-projected Bardeen–Cooper–Schrieffer wavefunction. We demonstrate our method for the single-band Fermi–Hubbard Hamiltonian in one and two dimensions. We also explore post-selection as a state preparation step to obtain correlated AGP and prove that it scales no worse than

O

(

M

)

in the number of measurements, thereby making it a less expensive alternative to gauge integration to restore particle number symmetry.