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Crystallization of battery-grade lithium carbonate with high recovery rate via solid-liquid reaction

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Particuology 2024年第9期92卷 95-105页

作者： Chaofan Wu Longjin Jiang Wei Wang Bin Dong Zhidong Chang Daixiang Wei hira Anwar Minghui Zhang Dekun Gao School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing100083China Anhui Chaoyue Environmental Protection Technology Co. LtdChuzhou239060China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China Anhui Huihong Technology Co. LtdChuzhou239060China

Lithium carbonate(Li_(2)CO_(3))stands as a pivotal raw material within the lithium-ion battery ***,we propose a solid-liquid reaction crystallization method,employing powdered sodium carbonate instead of its solution,which minimizes the water introduction and markedly elevates one-step lithium recovery *** kinetic calculations,the Li_(2)CO_(3)solid-liquid reaction crystallization process conforms by the Avrami equation rather than shrinking core model,which means the dissolution rate of Na_(2)CO_(3)is the most important factor affecting the reaction *** effects of reaction conditions such as temperature and stirring speed on the Li_(2)CO_(3)precipitation behavior were *** results indicated that temperature is a most essential parameter than other reaction conditions or stirring *** exceptional 93%recovery of Li_(2)CO_(3)at 90℃with a remarkable purity of 99.5%was achieved by using 1.2 M ratio of Na_(2)CO_(3)/Li_(2)SO_(4).This method provides a new idea for the efficient preparation of battery-grade Li_(2)CO_(3).

关键词： Lithium recovery Lithium sulfate Reaction crystallization Battery-grade lithium carbonate

An Adaptive Data-driven Method Based on Fuzzy Logic for Determining Power System Voltage Status

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 707-718页

作者： Sirwan Shazdeh Hêmin Golpîra Hassan Bevrani the SMGRC University of KurdistanSanandajIran Power Systems Modeling&Simulation Lab Department of Electrical EngineeringUniversity of KurdistanKurdistanSanandaj 66177-15175Iran

This paper proposes an adaptive method based on fuzzy logic that utilizes data from phasor measurement units(PMUs) to assess and classify generating-side voltage trajectories. The voltage variable and its associated derivatives are used as the input variables of a fuzzy-logic block. In addition, the voltage trajectory is compared with the pre-selected pilot-bus voltage to make a reliable decision about the voltage operational state. Different types of short-term voltage dynamics are considered in the proposed method. The fuzzy membership functions are determined using a systematic method that considers the current situation of the voltage trajectory. Finally, the voltage status is categorized into four classes to determine appropriate remedial actions. The proposed method is validated on a IEEE 73-bus power system in a MATLAB environment.

关键词： Fuzzy logic fault-induced delayed voltage recovery phasor measurement unit(PMU) short-term voltage stability situational awareness voltage classification

Recurrent acute pancreatitis as an initial presentation of primary hyperparathyroidism:A case report

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World Journal of Clinical Cases 2024年第29期12卷 6302-6306页

作者： Masood M Karim hira raza Om Parkash Department of Medicine The Aga Khan University HospitalKarachi 74800SindhPakistan Department of Surgery Aga Khan University HospitalKarachi 74800SindhPakistan

BACKGROUND With 4.9 to 35 instances per 100000 cases,hyperparathyroidism is one of the rarest causes of acute *** major cause of primary hyperparathyroidism is a parathyroid adenoma,which can manifest clinically in various *** SUMMARY We discuss the unusual case of a 13-year-old boy with recurrent pancreatitis as the initial presentation of primary *** cause of his recurrent pancreatitis remained unknown,and the patient had multiple admissions with acute pancreatitis over 3 *** diagnosis was delayed due to the initial normal levels of parathyroid hormone,which were later reported elevated in a subsequent episode where ultrasound neck and thyroid scintigraphy revealed a parathyroid adenoma as the underlying *** the diagnosis was made,he underwent surgical resection of the *** This case study stresses the importance of considering uncommon causes for recurrent pancreatitis.

关键词： Recurrent pancreatitis Primary hyperparathyroidism Normal serum parathyroid hormone Parathyroid adenoma Case report

Particle Size Optimization of Thermochemical Salt Hydrates for High Energy Density Thermal Storage

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Energy & Environmental Materials 2024年第2期7卷 326-333页

作者： Andrew Martin Drew Lilley raνi Prasher Sumanjeet Kaur Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Mechanical Engineering UC BerkeleyBerkeleyCA 94720USA

Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and ***,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy *** materials(TCMs)as a class of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high storage capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal ***,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of *** this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydrates during thermal *** is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the *** model is experimentally validated on multiple TCM salt hydrates with different water content,and effect of Rcrit on hydration and dehydration kinetics is also investigated.

关键词： high energy density hydration kinetics long-term cycling thermal energy storage thermochemical materials

粉末冶金Al-5.6Zn-2Mg合金在热压缩过程中加工硬化特性及本构模型的比较

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Journal of Central South University 2024年第2期31卷 346-368页

作者： KATIKA Harikrishna DAMODA R.K. DAVIDSON M.J. SEETHAraM R. KASAGANI veera Venkata Nagaraju Department of Mechanical Engineering National Institute of TechnologyWarangal 506004India Department of Mechanical Engineering The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Arrhenius模型、改进的Johnson-Cook模型(MJC)、改进的Zerilli-Armstrong模型(MZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Arrhenius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,MZA型模型和MJC型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Arrhenius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,MJC模型可能是一种更简单的替代方法。MZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,R值为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega,Kenya

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 932-939页

作者： Isabel Signes-Soler Alfred ragot Sheilah Nangena Andrew Wekesa raúl Montalbán Llamusí Department of Optics and Optometry and Vision Sciences Universidat de ValènciaBurjassotValencia 46010Spain NGO Vision Without Borders(Visio Sense Fronteres VSF)Calpe 03710AlicanteSpain Masinde Muliro University of Science and Technology P.O Box 190-50100KakamegaKenya Clinica Baviera Alicante C/Ausóy Monzó 16Alicante 03006Spain

AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community ***:The study was *** 3343 participants were included in the *** initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D *** inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVArange 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to *** the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye *** estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total *** around 0.18%of the total sample had hyperopia value exceeding+1.75 *** astigmatism(cilractive *** was detected in 0.66%(22/3343)of the screened *** was no statistically significant correlation observed between age or gender and refractive ***:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error *** findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI.

关键词： visual impairment refractive errors myopia amblyopia sustainable development goals

Four buildings and a flush:Lessons from degraded water quality and recommendations on building water management

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Environmental Science and Ecotechnology 2024年第2期18卷 104-113页

作者： Kyungyeon ra Caitlin Proctor Christian Ley Danielle Angert Yoorae Noh Tolulope Odimayomi Andrew J.Whelton Lyles School of Civil Engineering Purdue University550 Stadium Mall DriveWest LafayetteIN47907USA Agricultural and Biological Engineering Division of Environmental and Ecological EngineeringPurdue UniversityWest LafayetteIN47907USA Division of Environmental and Ecological Engineering Purdue UniversityWest LafayetteIN47907USA Civil and Environmental Engineering University of Colorado1111 Engineering DriveBoulderCO80309USA Civil Architectural and Environmental EngineeringUniversity of Texas301E E Dean Keeton StreetAustinTX78712USA Civil and Environmental Engineering Virginia Tech750 Drillfield DriveBlacksburgVA24061USA Lyles School of Civil Engineering Division of Environmental and Ecological EngineeringPurdue University550 Stadium Mall DriveWest LafayetteIN47907USA

A reduction in building occupancy can lead to stagnant water in plumbing,and the potential consequences for water quality have gained increasing *** investigate this,a study was conducted during the COVID-19 pandemic,focusing on water quality in four institutional *** of these buildings were old(>58 years)and large(>19,000 m2),while the other two were new(>13 years)and small(rarely detectable in cold/drinking water ***,the pH,dissolved oxygen,total organic carbon,and total cell count levels in the first draw of cold water samples were similar across all ***,the ranges of heavy metal concentrations in large buildings were greater than observed in small ***(Cu),lead(Pb),and manganese(Mn)sporadically exceeded drinking water limits at cold water fixtures,with maximum concentrations of 2.7 mg Cu L^(-1),45.4 mg Pb L^(-1),1.9 mg Mn L^(-1).Flushing the plumbing for 5 min resulted in detectable residual at fixtures in three buildings,but even after 125 min of flushing in largest and oldest building,no residual chlorine was detected at the fixture closest to the building's point of *** the pandemic,the building owner conducted fixture flushing,where one to a few fixtures were operated per visit in buildings with hundreds of fixtures and multiple ***,further research is needed to understand the fundamental processes that control faucet water quality from the service line to the *** the absence of this knowledge,building owners should create and use as-built drawings to develop flushing plans and conduct periodic water testing.

关键词： COVID-19 pandemic Stagnation Drinking water quality Flushing

Chi-square automatic interaction detection(CHAID)analysis of the use of safety goggles and face masks as personal protective equipment(PPE)to protect against occupational biohazards

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Journal of Biosafety and Biosecurity 2024年第2期6卷 125-133页

作者： raúl Aguilar-Elena Juán JoséAgún-González Universidad Internacional de Valencia ValenciaSpain

Background:This study represents the first Spanish investigation to rigorously evaluate compliance with the use of safety goggles and face masks as essential personal protective equipment(PPE)in companies with workplaces involving exposure to biological ***:This study aimed to examine the degree of use of face masks and safety goggles as personal protective equipment(PPE),the factors that influence their use,and the profile of workers exposed to occupational biological agents in Spanish companies in the health sector,farming sector,meat industry,waste treatment plants,food industry,and veterinary ***:We conducted a cross-sectional descriptive study involving 590 Spanish workers from 51 *** developed a 34-item questionnaire to assess workers’perception of risk related to exposure to biological agents in their *** the questions,three were designed to measure the degree of use of key protective equipment in sectors with biological agent exposure:protective gloves,safety goggles or face *** only analyzed safety goggles and face *** performed various statistical analyses,including Cronbach’s alpha,frequency of endorsement,content validity ratio using Lawshe’s method,varimax rotation,the Kaiser-Meyer-Olkin test,and Bartlett’s sphericity test,to assess the internal consistency and reliability of the ***,we employed a chi-square automatic interaction detection(CHAID)segmentation analysis,using workers’responses regarding their attitudes toward safety goggles and face mask usage as PPE for protection against biological risks,with demographic variables as independent ***:In the current study,CHAID analysis revealed that workers exposed to group 2 biological agents used more safety goggles and face shields compared with workers exposed to other groups of biological ***,workers in laboratories and the food industry used face masks more than workers of other ***

关键词： PPE Safety googles and breath mask CHAID Biological Agents Occupational Biosafety

Dosage and utilization of dexamethasone in the management of COVID-19: A critical review

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World Journal of Virology 2024年第3期13卷 107-114页

作者： Imran Sethi Asim Shaikh Musa Sethi hira Khalid Chohan Sheraz Younus Syed A Khan Salim Surani Department of Critical Care Medicine Marion General HospitalMarionIN 46952United States Department of Medicine Aga Khan UniversityKarachi 74200SindhPakistan Department of Medicine Eman SchoolFishersIN 46038United States Department of Internal Medicine Dow University of Health ScienceKarachi 74200SindhPakistan Department of Hospital Medicine Franciscan HealthIndianapolisIN 46237United States Department of Critical Care Medicine Mayo Clinic Health SystemMankatoMN 56001United States Department of Medicine and Pharmacology Texas A and M UniversityCollege StationTX 77843United States

BACKGROUND The severe respiratory manifestations observed in severe coronavirus disease 2019(COVID-19)cases are often associated with an excessive inflammatory ***,a synthetic glucocorticoid,exerts its anti-inflammatory effects by inhibiting the transcription of pro-inflammatory genes and suppressing the activity of various immune *** mechanism has implications for mitigating the cytokine storm observed in severe COVID-19 *** on in the pandemic,the Recovery Collaborative working group showed a mortality benefit of using dexamethasone in decreasing mortality in patients with COVID-19 requiring respiratory ***,the optimal dosage of corticosteroids remains *** studies that compare different doses of dexamethasone in COVID-19 exist,but the results are *** To review the latest evidence regarding dosage,safety,and efficacy of dexamethasone in severe *** We followed preferred reporting items for systematic reviews and meta-analysis guidelines.A detailed literature search was conducted across PubMed,Google Scholar,and Medline to include publications up to March *** keywords included“COVID-19”“SARS-CoV-2”“dexamethasone”“corticosteroid”“steroid”and“glucocorticoid”-along with their *** employed the Cochrane Risk of Bias Tool and the Newcastle-Ottawa scale to evaluate the integrity and potential of bias in the included studies.A meta-analysis was conducted using a random-effects model,assessing pooled odds ratios and mean differences,with heterogeneity gauged by the I2 statistic and theχ^(2) *** No statistical differences were found in 28-day all-cause mortality[pooled odds ratio(OR)=1.109,95%CI:0.918-1.340],60-day all-cause mortality(OR=0.873,95%CI:0.744-1.024;I2=47.29%),mean length of hospital stay(mean difference=-0.08 days,95%CI:-0.001 to 0.161)and adverse events(OR=0.877,95%CI:0.707-1.087).CONCLUSION Differing doses of corticosteroids have no clinical implication

关键词： COVID-19 Steroids Corticosteroids Steroid dosage Critical care Corona virus