bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Model for Predicting the Maximum Gas Entrapment Concentration in a Yield Stress Fluid
Authors: Pan Shaowei , Wang Zhiyuan , Sun Baojiang 
Published: January 2022

Summary
Gas entrapment is a typical phenomenon in gas-yield stress fluid two-phase flow, and most of the related research focuses on the entrapped condition of the single bubble. However, the amount of entrapped gas, which is more meaningful for engineering, is rarely involved. In this paper, a theoretical model for calculating the maximum gas entrapment concentration (MGEC) is established for the first time. The critical distance between horizontal and vertical entrapped bubbles was determined by the yielded region caused by the buoyancy and the coupled stress field around the multiple bubbles. The MGEC is the ratio of a single bubble volume to its domain volume, which is calculated from the distance between the vertical and the horizontal bubbles. By comparing with the experimental results, the average error of MGEC calculated by this model is 4.42%, and the maximum error is 7.32%. According to the prediction results of the model, an empirical equation that can be conveniently used for predicting MGEC is proposed.
Effect of 2D Alpha-Zirconium Phosphate Nanosheets in Interfacial Tension Reduction and Wettability Alteration: Implications for Enhanced Oil Recovery
Authors: Qing Song , Chen Hong , Han Li-juan , Ye Zhongbin , Liao Yihao , Luo Yang , Zhang Faxue , Wang Jingfan , Yang Ning 
Published: January 2022

Summary
α-Zirconium phosphate (α-ZrP) nanocrystals were synthesized by refluxing method and subsequently exfoliated into extremely thin 2D nanosheets by tetrabutylammonium hydroxide (TBAOH) solution. Dynamic light scattering, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the size distribution and morphology of α-ZrP nanosheets. Interfacial tension (IFT) and contact angle measurement were conducted by different concentrations of α-ZrP nanosheets solutions. The results displayed that the wettability of porous media surface was altered from oleophilic to hydrophilic and the IFT decreased with the increasing of α-ZrP nanosheets concentrations. A new method was proposed to calculate the Hamaker constant for 2D α-ZrP nanosheets. The calculated results displayed that α-ZrP nanosheets were not easy to agglomerate under experimental environment and when the interaction energy barrier increased, the transport amount of α-ZrP nanosheets also increased. Coreflooding tests were also performed with various concentrations and the oil recovery efficiency increased from 33.59 to 51.26% when α-ZrP nanosheets concentrations increased from 50 to 1,000 ppm.
Modified Corn Starch as an Environmentally Friendly Rheology Enhancer and Fluid Loss Reducer for Water-Based Drilling Mud
Authors: Ricky Emanuel , Mpelwa Musa , Wang Chao , Hamad Bahati , Xu Xingguang 
Published: January 2022

SummaryDrilling fluid rheology and fluid loss property are fundamental parameters that dictate the effectiveness and easiness of a drilling operation. Maintaining these parameters under high temperatures is technically challenging and has been an exciting research area for the drilling industry. Nonetheless, the use of drilling mud additives, particularly synthetic polymers, threaten ecological environments. Herein, modified corn starch (MCS) was synthesized, characterized, and investigated as an environmentally friendly rheology enhancer and filtration loss controlling agent for water-based mud (WBM) at high temperatures. The experimental results indicated that MCS exhibits better performance in improving rheological properties and fluid loss controlling ability for WBM than the commonly used mud additives. With the addition of an optimal concentration (0.3 wt%), MCS improved the rheology and fluid loss behavior of WBM formulation at harsh aging temperature (220°C) by practically 4 times and 1.7 times, respectively. The MCS was revealed to perform superbly over polyanionic cellulose (PAC) addition at all investigated temperatures. The better performance of the MCS was ascribed to the improved entanglements in the mud system owing to the additional hydroxyl (OH) groups. Besides, the Herschel-Bulkley model was found to be a constitutive model that described the rheological properties of the investigated muds satisfactorily. Moreover, the MCS was found to exhibit acceptable biodegradability properties.
Fabrication of Fe-doped ZnO/Nanocellulose Nanocomposite as an Efficient Photocatalyst for Degradation of Methylene Blue Under Visible Light
Authors: Farahani Mohammad Saeed Vasheghani , Nikzad Maryam , Ghorbani Mohsen 
Published: January 2022

Abstract
In this work, a photocatalytic nanocomposite, Fe-doped ZnO/nanocellulose, was synthesized using an in-situ method and examined for methylene blue (MB) degradation. For this purpose, pure ZnO (PZ) was synthesized by the chemical precipitation method and then subjected to Fe+3 doping with different concentrations of Fe3+ (1, 3, and 5 mol%). The PZ and Fe-doped ZnO (FZ) samples were characterized using several standard analyses. UV-vis DRS analysis was also used to investigate the effect of Fe3+ doping on the bandgap of PZ. The doping of Fe3+ enhanced the photocatalytic activity of ZnO under visible light. The degradation efficiency of FZ samples (> 50%) was enhanced compared to the pristine ZnO (36.91%) during the same period. The catalyst with the highest degradation efficiency (94.21%) was then conjugated with broom corn stalk-derived nanocellulose (NC) at varying NC/ Zn2+ molar ratios (0.1, 0.2, 0.3, and 0.4) and characterized by various analyses. The NC enhanced the hydroxyl group at the surface of the nanocomposite, consequently improved the photocatalytic performance of the synthesized samples. The ability of the optimized photocatalyst for MB degradation was assessed. The effect of operating parameters such as pH, catalyst dosage, and initial MB concentration was investigated and degradation efficiency of 98.84% was achieved at the optimum condition. Besides, photocatalyst regeneration study indicated the great photocatalytic performance of this nanocomposite with no loss in its degradation efficiency. The facile synthesis and fast degradation rate of this nanocomposite make it a promising candidate for real-world wastewater treatment.
Caving Impacts on Cave Microbial Diversity: Case Study of Morca Cave, Turkey
Authors: RACHID Nahdhoit AHAMADA , Güngör Nihal Doğruöz 
Published: January 2022

Abstract
Some microorganisms identified in cave ecosystems have been reported to play a permanent and significant role for maintaininglife in such environments. Human entrance into caves can induce some changes on cave physic-ochemical parameters which altimately affects the living organisms. In this regard, for the first time, Morca Cave was explored to evaluate the impacts that human activities may have on the microbial diversity of the cave in a limited period of time. During this expedition at a depth of 1040 m, a camp was established for four days. Before the installation and at the end of the camp, sediments and surface samples were taken from different points of the camp area and the area around it. Sequencing of 16s rRNA of each sample was performed using the next generation sequencing method. The profile of the microbial diversity before the camping reaveled that Thermoplasmata dominated the archaea group and Gamma- and Alpha-proteobacteria were the most dominant bacterial group. After the camp, a decrease in the microbial diversity especially the previously mentioned classes strains is observed at the most of the sampled areas. The results also showed that Bacilli strains significantly increased after the camp and increase of Bacteroidia strains is observed at the most active sampled areas. This present study therefore highlights how microbial diversity inside a closed cave can respond to the human activities within a short period. Furthermore, it may constitute a solid basis to support efforts targeted at improving technics for cave management and expedition for the conservation of cave nature.
Investigation of Er:YAG laser-activated irrigation for the removal of biofilm and observations of laser-induced cavitation behavior
Authors: Nagahashi Taiji , Yahata Yoshio , Handa Keisuke , Nakano Masato , Suzuki Shigeto , Kakiuchi Yusuke , Tanaka Toshinori , Kanehira Masafumi , Venkataiah Venkata Suresh , Saito Masahiro 
Published: January 2022

Abstract
Background

We investigated the biofilm removal effects of LAI using a pig model, focusing on the impact of the fiber tip position, and used a high-speed camera to observe the occurrence and positioning of the cavitation associated with laser irradiation.
Methods

A total of 16 roots of deciduous mandibular second premolars from 4 pigs were used. After a pulpectomy, the canals were left open for two weeks and sealed for 4 weeks to induce intraradicular biofilm. Then, root canal irrigation was performed with Er:YAG laser activation. The fiber tip was inserted at two different positions, i.e., into the root canal in the intracanal LAI group and into the pulp chamber in the coronal LAI group. Intracanal needle irrigation with saline or 5% NaOCl was utilized in the positive control and CNI groups. SEM and qPCR were carried out to evaluate treatment efficacy. For qPCR, ANOVA and a Tukey-Kramer post hoc test were performed with α = 0.05. A high-speed camera was used to observe the generation of cavitation bubbles and the movement of the induced bubbles after laser irradiation.
Results

The intracanal and coronal LAI groups showed significantly lower amounts of bacteria than either the positive control or CNI groups. There was no significant difference found between the intracanal and coronal LAI groups. SEM images revealed opened dentinal tubules with the destruction of biofilm in both LAI groups. High-speed camera images demonstrated cavitation bubble production inside the root canal after a single pulse irradiation pulse. The generated bubbles moved throughout the entire internal multi-rooted tooth space.
Conclusions

Coronal LAI can generate cavitation in the root canal with a simply placed fiber inside the pulp chamber, leading to effective biofilm removal. This method could thus contribute to the future development of endodontic treatments for refractory apical periodontitis caused by intraradicular biofilm.
A Comparison of Pollution, Environmental Hazards, Sedimentology, and Geochemistry, in Five Economic Harbors Along the Egyptian Coast of Mediterranean Sea
Authors: El-Sadaawy Manal , El-Said Ghada F. , Khalil Mona , Morsy Fadia A.M. , Draz Suzan E.O. 
Published: January 2022

Abstract
Heavy metal pollution and its environmental and human risks have become one of the most important global environmental problems. In the current study, the potential heavy metals ecological risks and their pollution status were assessed in five important harbors (Sidi Krir, Dekhila, Western, Damietta, and Port Said) along the Egyptian coast of the Mediterranean Sea. Twenty-six sediment samples were collected from five harbors, where eight heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, Pb and Cd) were identified as well as their texture and geochemistry. To gain deeper insights into the human and ecological hazards of the heavy metals, thirteen ecological indices, sediment quality guidelines and multivariate analysis as well as two pathways of exposures to non- carcinogenic and carcinogenic risk of heavy metals for children and adults were evaluated. The data shown that Sidi Kriri harbor recorded the lowest values for heavy metals, for Cu, while Western Harbor had the highest average for Zn Multivariate analysis revealed the contribution of heavy metals to sediment contamination and the geochemical characteristics as well as nearby sources of pollution. Geo-accumulation index, Contamination factor, Toxic units, sum of toxic units, sediment modified hazard quotient, and sediment hazard quotients reflected the significant contribution of Cd to sediments along all harbors. Non-carcinogenic hazard risk index (HI) values along the harbors gave the order: Western> Port Said> Damietta> Dekhila> Sidi Krir. Also, TLCR values for children and adults indicated the irregularly high abundance of heavy metals in harbor sediments that may cause adverse public health effects.
Venus’ light slab hinders its development of planetary-scale subduction and habitability
Authors: Chen Junxing , Jiang Hehe , Tang Ming , Hao Jihua , Tian Meng , Xu Chu 
Published: January 2022

Abstract
Terrestrial planets Venus and Earth have similar sizes, masses, and bulk compositions, but only Earth developed planetary-scale plate tectonics. Plate tectonics generates weatherable fresh rocks and transfers surface carbon back to Earth’s interior, which provides a long-term climate feedback, serving as a thermostat to keep Earth a habitable planet. Yet Venus shares a few common features with early Earth, such as stagnant-lid tectonics and the possible early development of a liquid ocean. Given all these similarities with early Earth, why would Venus fail to develop global-scale plate tectonics? In this study, we explore solutions to this problem by examining Venus’ slab densities under hypothesized subduction-zone conditions. Our petrologic simulations show that eclogite facies may be reached at greater depths on Venus than on Earth, and Venus’ slab densities are consistently lower than Earth’s. We suggest that the lack of sufficient density contrast between the high-pressure metamorphosed slab and mantle rocks may have impeded self-sustaining subduction. Although plume-induced crustal downwelling exists on Venus, the dipping of Venus’ crustal rocks to mantle depth fails to transition into subduction tectonics. As a consequence, the supply of fresh silicate rocks to the surface has been limited. This missing carbon sink eventually diverged the evolution of Venus’ surface environment from that of Earth.
Simulation of Contaminants Transport in Groundwater From Nickel Mining Waste Dump Southeast Sulawesi
Authors: Setiawan Kadek Nando , Cahyadi Tedy Agung , Amri Nur Ali , Ernawati Rika , Nurkhamim Nurkhamim , Ansori Muhammad Iqbal , Firmansyah Ilham , Makarao Sri Lastri 
Published: January 2022

Abstract
The irregularities of nickel resource mining in Indonesia cause many serious environmental problems. Piles of leftover rocks on nickel mining waste dumps have the potential to be a source of heavy metal seepage into the water. This study was conducted to assess the impact of nickel mining in the Langgikima Subdistrict of the North Konawe Regency of Southeast Sulawesi Province. The focus is to assess the migration of hexavalent chromium (Cr6+) and iron (Fe) using MT3DMS to model the transport of solutes. The study's goal was to identify cr6+ and Fe concentrations in waste dumps and predict the spread of contaminants over a 20-year period of time. XRF (X-Ray Fluorescence) is done to determine the content of elements and minerals in rocks. Toxicity Characteristics Leaching Procedure (TCLP) is performed to estimate the concentration of Cr6+ and Fe in waste dumps. AAS (Atomic Absorption Spectrophotometer) to find out the content of Cr6+ and Fe in surface water and land water samples. The results showed the highest concentrations of Cr6+ of 0.0462 mg/L and Feat 0.8709 mg/L. Simulations without compacted clay coatings, Cr6+ and Fe contaminants could be transported consecutively by 2.7 km and 2.42 km while simulations used compacted clay layers with a hydraulic conductivity of 1 × 10−9 m/s of Cr6+ and Fe contaminants could be transported consecutively by 0.412 km and 0.467 km. It can therefore be concluded that heavy metals in the remaining rock piles from the waste dump can be transported into groundwater, and the action of using a compacted layer of clay must be taken to prevent contaminant migration into groundwater.
Energy and Environmental Analysis of a Solar Evacuated Tube Heat Pipe Integrated Thermoelectric Generator Using IoT
Authors: Manivannan SakthiPriya , Gunasekaran DivyaLaxmi , Jaganathan Gowthami , Natesan Shanthi , Muthusamy SabariMuthu , Kim Sung Chul , Kumar Balaji , Poongavanam GaneshKumar , Duraisamy Sakthivadivel 
Published: January 2022

Abstract
This paper investigates the solar evacuated tube heat pipe system (SEHP) coupled with a thermoelectric generator (TEG) using the internet of things (IoT). The TEGs convert heat energy into electricity through the Seebeck effect that finds application in the waste heat recovery process for the generation of power. The present work deals with the theoretical study on solar evacuated tube heat pipe integrated TEG and it is validated experimentally using with and without parabolic trough concentrating collector. And the carbon credit of the TEG system is determined to find its potential in the environmental aspect. Also, the boost type converter is used to raise the power output by increasing the voltage from the TEG for rural electrifications. However, it is found that the maximum power output due to the influence of the parabolic trough concentrator results in increased efficiency when compared with the non-concentrating SEHP-TEG system. The TEG output power can be boosted up to a maximum of 5.98 V using a power electronic boost converter. Besides, the recorded real sensor data with Arduino is implemented in the experimental process for automatic remote monitoring of the temperature.
Epidemiological Characteristics of Traumatic Spinal Cord Injuries in Multi-Center Retrospective Study in Northwest China, 2017-2020.
Authors: Wang Xiaohui , Jiang Chao , Du Jinpeng , Zhang Yongyuan , Tian Fang , Chen Zhe , Zhang Yuyang , Wang Zhiyuan , Zhang Ying , Yan Liang , Hao Dingjun 
Published: January 2022

Abstract
Introduction: Traumatic spinal cord injuries (TSCI) are worldwide public health problems. There has been a lack of extensive multi-center study of TSCI epidemiology in Northwest China in pre- and post-pandemic period of COVID-19. Materials and Methods: A multi-center retrospective study of 14 hospitals of Northwest China was conducted on patients with TSCI between 2017 and 2020. Variables assessed included patient demographics, etiology, segmental distribution, treatment, waiting time for treatment and outcomes.Results: The number of patients with TSCI showed an increasing trend from 2017 to 2019 while there were fewer patients in 2020 than in 2019. The male-to-female ratio was 3.67:1 and the mean age was 48±14.9. The major cause of TSCI was high fall (38.8%), low fall (27.7%), traffic accidents (23.9%), sports (2.6%) and others (7.0%). The segmental distribution showed a bimodal pattern, peak segments were C6 and Tl1, L1(14.7%) was the most frequently injured segments. Incomplete injury (72.8%) occurred more often than complete injury (27.2%). ASIA scale of most patients did not change before and after treatment both in operational or conservative group. 975 patients from urban and 1646 patients from rural areas were conducted, most urban residents could rush to get treatment after injured immediately (<1 h), whereas most rural patients get treatment spend several hours since injured. The rough annual incidence from 2017-2020 are 112.4, 143.4,152.2 and 132.6 per million people calculated by the population-coverage-rate.Conclusion: The incidence of TSCI in Northwest China is high and growing. However, under the pandemic policy reasons, it has decreased in 2020. The promotion of online work may be an effective primary prevention measures for trauma. Also, due to the distance from the hospitals with proper conditions, rural patients need to spend long time to there, the timely treatment of them should be paid attention.
Cellular and Humoral Responses to SARS-CoV-2 Vaccination in Immunosuppressed Patients
Authors: Mohanraj Dinesh , Baldwin Samuel , Singh Satbeer , Gordon Alun , Whitelegg Alison 
Published: January 2022

Abstract
Objective: SARS-CoV-2 vaccinations have demonstrated vaccine-immunogenicity in healthy volunteers, however, efficacy in immunosuppressed patients is less well characterised. There is an urgent need to address the impact of immunosuppression on vaccine immunogenicity. Methods: Serological, T-cell ELISpot, cytokines and immunophenotyping assays were used to assess vaccine responses (either BNT162b2 mRNA or ChAdOx1 nCoV-19) in double-vaccinated patients receiving immunosuppression for renal transplants or haematological malignancies (n=13). Immunological responses in immunosuppressed patients (VACC-IS) were compared to immunocompetent vaccinated (VACC-IC, n=12), unvaccinated (UNVACC, n=11) and infection-naïve unvaccinated (HC, n=3) cohorts. All participants, except HC, had prior COVID-19 infection. Results: T-cell responses were identical between VACC-IS and VACC-IC (92%) to spike-peptide (S) stimulation. UNVACC had the highest T-cell non-responders (n=3), whereas VACC-IC and VACC-IS both had one T-cell non-responder. No significant differences in humoral responses were observed between VACC-IC and VACC-IS, with 92% (12/13) of VACC-IS patients demonstrating seropositivity. One VACC-IS failed to seroconvert, however had detectable T-cell responses. All VACC-IC participants were seropositive for anti-spike antibodies. VACC-IS and VACC-IC participants elicited strong Th1 cytokine response with immunodominance towards S-peptide. Differences in T-cell immunophenotyping were seen between VACC-IS and VACC-IC, with lower CD8+ activation and T-effector memory phenotype observed in VACC-IS. Conclusion: SARS-CoV-2 vaccines are immunogenic in patients receiving immunosuppressive therapy, with responses comparable to vaccinated immunocompetent participants. Lower humoral responses were seen in patients treated with B-cell depleting therapeutics, but with preserved T-cell responses. We suggest further work to correlate both protective immunity and longevity of these responses in both healthy and immunosuppressed patients.
Ground Subsidence Response Conditional On Large-Scale Geothermal Exploitation In A Karst Reservoir Area of North China
Authors: Yao Yahui , Jia Xiaofeng , Li Shengtao , Zhang Qiuxia , Song Jian , Xiang Hong , Wang Junzhao 
Published: January 2022

Abstract
Carbonate karst geothermal resources are widely distributed and have large reserves in North China. Nowadays, the scale of exploitation and utilization of the carbonate karst geothermal resources is gradually increasing. In this work, a geothermal exploitation area where the karst geothermal reservoirs are exploited on a large scale, is selected as the study area, and methods including experiment and numerical simulation are used to study the exploitation-induced ground subsidence problems based on the long-term water level monitoring data of the geothermal reservoir. Through analyses of ground subsidence caused by water level change of the geothermal reservoir, the following conclusions were obtained. The water level drawdown of different types of geothermal reservoirs had different effects on ground subsidence. The maximum ground subsidence of the study area caused by the water level decline of the Jx w carbonate geothermal reservoir was only 0.29 mm/a from 1983 to 2019, which is generally insignificant. In contrast, the same water level change of the N m sandstone geothermal reservoir was predicted to cause 8.9 mm/a ground subsidence. To slow down or even prevent the ground subsidence, balanced production and reinjection are required. From the result of this work, the decline of the water level of the Jx w carbonate geothermal reservoir caused by current large-scale geothermal exploitation will not cause serious ground subsidence. However, attention should be paid to the N m sandstone type geothermal reservoirs as their structures are much more sensitive to the water pressure change.