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Nanofluid based on 1-dodecylpyridinium chloride for enhanced oil recovery

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Petroleum Science 2023年第1期20卷 600-610页

作者： akram Al-Asadi Alba Somoza Alberto Arce Eva Rodil Ana Soto CRETUS.Department of Chemical Engineering Universidade de Santiago de CompostelaE-15782Santiago de CompostelaSpain Chemical and Petrochemical Techniques Eng.Department Basra Engineering Technical CollegeSothern Technical UniversityMinistry of Higher Education and Scientific ResearchIraq School of Engineering Universidade de A CorunaE-15403FerrolSpain

The use of nanoparticles is considered promising for enhanced oil recovery(EOR),especially when they are combined with ***,the combination of nano-sized material with surface-active ionic liquids(SAILs)is an unexplored EOR *** this work,the advantages of mixing Al2O3 nanoparticles with the SAIL 1-dodecylpyridinium chloride were *** nanofluids in brine could only be achieved using the polymer polyvinylpyrrolidone(PVP)as a stabilizing *** was found that the addition of nanoparticles(and PVP)to the surfactant formulation helped to:slightly increase its viscosity,enhance its water-oil interfacial tension(IFT)reduction capacity,and reduce the adsorption on carbonate rocks(adsorption on sandstone was found to be excessive).IFT was selected as target property to minimize for the design of EOR *** flooding tests were carried out with surfactant(0.5 wt%[C_(12)py]Cl),surfactant-polymer(0.5 wt%[C_(12)py]Cl,1.0 wt%PVP)and nanofluid(0.05 wt%Al_(2)O_(3),1.0 wt%PVP,0.5 wt%[C12py]Cl)formulations in brine(0.5 wt%NaCl).Additional oil recoveries of 3.4%,7.4%and 12.0%OOIP were achieved,respectively,the nanofluid formulation being the most promising for the ***,it was found capable of changing the wettability of carbonate rocks from oilwet to *** significance of this work lies in showing the new possibilities resulting from the combination of SAILs and nanoparticles for EOR,specifically the combination of[C_(12)py]Cl with Al_(2)O_(3).

关键词： Nanofluid Viscosity Interfacial tension Adsorption Wettability EOR

Significantly enhanced flashover voltage of epoxy in vacuum by graded surface roughness modification

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High Voltage 2023年第5期8卷 997-1010页

作者： Inzamam Ul Haq Feipeng Wang Shakeel akram Muneeb Ahmed Muhammad Tariq Nazir State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjingChina State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina School of Engineering RMIT UniversityMelbourneVictoriaAustralia

The flashover strength of epoxy(EP)insulations in the High voltage direct current applications of future energy grids can be improved by tailoring their surface *** work aims to improve the DC surface flashover characteristics of EP after being treated with sandpaper of different *** with virgin EP and homogenously modified EP considering varying surface roughness(R_(a)=0.54,3.16,5.24,and 8.35μm)are *** experimental characterisations,such as water contact angle,surface intrinsic conductivity,surface voltages,flashover strength,and trap distributions are conducted and evaluated to analyse the difference between virgin and treated ***,based on the obtained experimental results of homogenously treated EP and theoretical analysis,the concept of surface functionally graded materials(SFGMs)is put *** flashover voltages of homogenously treated EP are augmented significantly compared to virgin EP regardless of the voltage polarity and enhanced by enhancing the surface *** sample T_(Model‐C) with SFGM design shows a 45.02%and 43.75%improvement in the negative and positive flashover voltages than that of the virgin *** the end,COMSOL simulations are conducted to justify the experimental findings and to analyse the difference between virgin and modified samples in terms of electric field distribution.

关键词： flash graded roughness

后路有限切开减压植骨联合经皮椎弓根螺钉内固定治疗胸腰椎C型骨折的疗效

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中华创伤杂志 2024年第4期40卷 343-349页

作者：韩念荣艾克热木·吾斯曼刘岩路莫军王荣胡炜黄异飞新疆医科大学附属中医医院脊柱二科乌鲁木齐830000

目的:比较后路有限切开减压植骨联合经皮椎弓根螺钉与传统后路切开减压植骨联合椎弓根螺钉内固定治疗胸腰椎C型骨折的疗效。方法:采用回顾性队列研究分析2015年1月至2019年12月新疆医科大学附属中医医院收治的60例胸腰椎C型骨折患者的... 详细信息

目的:比较后路有限切开减压植骨联合经皮椎弓根螺钉与传统后路切开减压植骨联合椎弓根螺钉内固定治疗胸腰椎C型骨折的疗效。方法:采用回顾性队列研究分析2015年1月至2019年12月新疆医科大学附属中医医院收治的60例胸腰椎C型骨折患者的临床资料,其中男37例,女23例;年龄25~61岁[(46.5±9.8)岁]。损伤节段:T 10~11 11例,T 11~12 12例,T 12~L 1 19例,L 1~2 9例,L 2~3 9例。美国脊髓损伤协会(ASIA)分级:A级27例,B级21例,C级12例。30例行后路有限切开减压植骨联合经皮椎弓根螺钉内固定(微创手术组),30例行传统后路切开减压植骨联合椎弓根螺钉固定(传统切开组)。比较两组手术时间、术中出血量;术前,术后1周、6个月及末次随访时矢状面Cobb角、伤椎前缘高度、视觉模拟评分(VAS)、Oswestry功能障碍指数(ODI);末次随访时ASIA分级;术中及术后并发症发生率。结果:患者均获随访35~46个月[(39.0±3.4)个月]。微创手术组手术时间为150(120,210)min,术中出血量为145(100,200)ml,短于或少于传统切开组的210(210,240)min、330(300,350)ml( P0.05)。术后1周、6个月微创手术组VAS分别为3.0(2.0,4.0)分、1.0(1.0,2.0)分,低于传统切开组的4.0(4.0,5.0)分、2.0(1.0,2.0)分( P0.05)。术中及术后微创手术组并发症发生率为10.0%(3/30),低于传统切开组的33.3%(10/30)( P<0.05)。结论:与传统后路切开减压植骨联合椎弓根螺钉相比,后路有限切开减压植骨联合经皮椎弓根螺钉内固定治疗胸腰椎C型骨折具有手术时间短、术中出血量少、术后早期疼痛缓解明显和并发症发生率低等优势。

关键词：脊柱骨折胸椎腰椎骨移植骨折固定术内

温度对酶促聚对苯二甲酸乙二醇酯降解的影响分析

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Chinese Journal of Catalysis 2024年第5期60卷 284-293页

作者：伊科拉木·艾克然木曹宇飞邢皓丁于敬罗宇政韦韧张一飞北京化工大学化工资源有效利用国家重点实验室北京100029 北京化工大学北京软物质科学与工程高精尖创新中心北京100029 华南理工大学食品科学与工程学院应用生物催化实验室广东广州510640 格赖夫斯瓦尔德大学生物化学研究所格赖夫斯瓦尔德德国

近年来,聚对苯二甲酸乙二酯(PET)的酶法降解及循环利用备受关注.PET的酶法降解是在不可溶聚合物表面发生的界面催化过程,酶通过水解PET聚合物表面上可及的酯键,将聚合物逐渐分解成单体.反应温度可以从酶的催化活性、热稳定性以及PET材... 详细信息

近年来,聚对苯二甲酸乙二酯(PET)的酶法降解及循环利用备受关注.PET的酶法降解是在不可溶聚合物表面发生的界面催化过程,酶通过水解PET聚合物表面上可及的酯键,将聚合物逐渐分解成单体.反应温度可以从酶的催化活性、热稳定性以及PET材料的生物可降解性等多个方面影响PET的降解过程,是影响PET酶法降解效果的主要因素之一.深入了解温度对PET酶降解过程的热力学和动力学调控机制,对PET降解酶的发掘与改造和酶法降解工艺的优化具有重要意义.本文以叶枝堆肥角质酶(LCC)的突变体WCCG为例,详细研究了温度对WCCG降解低结晶度PET(结晶度7.6%)和高结晶度(结晶度30%)PET微颗粒的影响.通常认为PET的酶促降解需要在其玻璃化转变温度(Tg,~70℃)附近或以上进行.实验测定了不同温度下的降解速率,并利用阿伦尼乌斯公式作图.结果表明,当反应温度在45℃(低于通常认为的Tg,b值约20℃)附近时,反应活化能突然降低,说明此时PET微颗粒表面的玻璃化转变已经开始,酶促降解已经能够有效进行,表现出酶解PET的界面催化特征.当温度高于75℃时,PET降解速率迅速降低,酶受热失活.研究还发现,WCCG存在热激活现象:通过将WCCG在不同温度下温育一段时间后在60℃下进行活性测定,WCCG在50-70℃范围内温育后活性显著提高;在70℃下温育4 h后其降解低结晶度PET的活性提高约1倍,同时对小分子底物4-硝基苯酚丁酯的活性也有明显提高.利用圆二色光谱和荧光光谱检测了WCCG的二级和三级结构变化.结果表明,热处理后的WCCG中的α-螺旋含量显著减少而β折叠含量增加,酶分子疏水性提高,这与分子动力学模拟结果一致.单分子力谱测试结果表明,热处理后的WCCG较处理前的酶与PET薄膜之间的粘附力从88 pN提高到150 pN.因此,WCCG的热激活是其本征催化活性改善和酶与PET表面吸附力增强共同作用的结果.WCCG在高结晶度PET的降解中也存在类似热激活现象.此外,在长时间的降解反应中,无定形区域的PET链段在相对较高的降解温度下逐渐进一步结晶,导致酶催化降解速率随着降解时间的延长而下降.综上所述,温度对酶催化PET降解过程的主要影响包括:PET表面的玻璃化转变、酶的热激活、酶的热失活、温度导致的PET材料再结晶,这些因素相互交织,说明酶促PET降解的温度依赖的复杂性.未来的研究除了继续挖掘和设计高活性、高稳定的PET水解酶外,还应提高酶在45到70℃范围内的催化活性并关注降解工艺的优化.

关键词：聚对苯二甲酸乙二酯酶法降解酶的热激活活化能表面玻璃化转变

Effects of native and invasive Prosopis species on topsoil physiochemical properties in an arid riparian forest of Hormozgan Province,Iran

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Journal of Arid Land 2022年第10期14卷 1099-1108页

作者： Maryam MOSLEHI JOUYBARI Asgahr BIJANI Hossien PARVARESH Ross SHACKLETON akram AHMADI Research Division of Natural Resources Hormozgan Agricultural and Natural Resources Research and Education CenterAgricultural ResearchEducation and Extension Organization(AREEO)Bandar Abbas ***Iran Department of Environmental Sciences Bandar Abbas BranchIslamic Azad UniversityBandar Abbas ***Iran Swiss Federal Institute for Forest Snow and Landscape Research(WSL)Birmensdorf 8903Switzerland Centre for Invasion Biology Department of Botany&ZoologyStellenbosch UniversityStellenbosch 7602South Africa Research Division of Natural Resources Golestan Agricultural and Natural Resources Research and Education CenterAgricultural ResearchEducation and Extension Organization(AREEO)Gorgan ***Iran

Biological invasions can alter soil properties within the range of their introduced,leading to impacts on ecosystem services,ecosystem functions,and *** better understand the impacts of biological invasions on soil,we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora),native tree species(Prosopis cineraria,Acacia tortilis,and Acacia ehrenbergiana),and mixed tree species in Hormozgan Province of Iran in May *** this study,we collected 40 soil samples at a depth of 10 cm under single tree species,including ***,***,***,and ***,as well as under mixed tree *** results showed that organic matter,moisture,potassium,calcium,nitrogen,and magnesium in topsoil at sites with *** and *** growing in combination with *** were higher than that at sites where *** was present(P<0.05).Sodium at sites with *** and *** growing in combination with *** and *** was lower as compared to that at sites with just *** and *** conductivity was lower at sites with *** and *** growing in combination with ***,and it was higher at sites with mixed Acacia and *** *** on the generally more positive effect of native Acacia and *** on topsoil physiochemical properties as compared to the ***,afforestation with native tree species is preferable for soil *** addition,due to the negative effects of *** on soil properties,*** spread should be better managed.

关键词： Prosopis juliflora Prosopis cineraria tree species invasion topsoil physiochemical properties Iran

A classification of genes involved in normal and delayed male puberty

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Asian Journal of Andrology 2023年第2期25卷 230-239页

作者： Maleeha akram Syed Shakeel Raza Rizvi Mazhar Qayyum David J Handelsman Department of Zoology Wildlife and FisheriesPir Mehr Ali Shah Arid Agriculture University RawalpindiShamsabadMurree RoadRawalpindi 46300Pakistan Andrology Laboratory The ANZAC Research InstituteHospital RoadConcordNSW 2139Australia

Puberty is a pivotal biological process that completes sexual maturation to achieve full reproductive *** is a major transformational period of life,whose timing is strongly affected by genetic makeup of the individual,along with various internal and external *** the exact mechanism for initiation of the cascade of molecular events that culminate in puberty is not yet known,the process of pubertal onset involves interaction of numerous complex signaling pathways of hypothalamopituitary-testicular(HPT)*** developed a classification of the mechanisms involved in male puberty that allowed placing many genes into physiological *** include(i)hypothalamic development during embryogenesis,(ii)synaptogenesis where gonadotropin releasing hormone(GnRH)neurons form neuronal connections with suprahypothalamic neurons,(iii)maintenance of neuron homeostasis,(iv)regulation of synthesis and secretion of GnRH,(v)appropriate receptors/proteins on neurons governing GnRH production and release,(vi)signaling molecules activated by the receptors,(vii)the synthesis and release of GnRH,(viii)the production and release of gonadotropins,(ix)testicular development,(x)synthesis and release of steroid hormones from testes,and(xi)the action of steroid hormones in downstream effector *** in components of this system during embryonic development,childhood/adolescence,or adulthood may disrupt/nullify puberty,leading to long-term male infertility and/or *** review provides a list of 598 genes involved in the development of HPT axis and classified according to this ***,this review identifies a subset of 75 genes for which genetic mutations are reported to delay or disrupt male puberty.

关键词： delayed puberty gonadotropin releasing hormone hypogonadism male puberty puberty testosterone

Cost and Efficiency Analysis of Steganography in the IEEE 802.11ah IoT Protocol

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Computers, Materials & Continua 2022年第8期72卷 3929-3943页

作者： akram A.Almohammedi Vladimir Shepelev Sam Darshi Mohammed Balfaqih Fayad Ghawbar Automobile Transportation Department South Ural State UniversityChelyabinsk454080Russia Electrical and Electronics Engineering Department Karabük University Karabük78050Turkey Department of Electrical Engineering Indian Institute of Technology RoparPunjab140001India Department of Computer and Network Engineering University of JeddahJeddah23218Saudi Arabia Faculty of Engineering Technology University Tun Hussein Onn MalaysiaPagoh Campus86400Malaysia

The widespread use of the Internet of Things(IoT)applications has enormously increased the danger level of data leakage and theft in IoT as data transmission occurs through a public *** a result,the security of the IoT has become a serious challenge in the field of information *** on the network is a critical tool for preventing the leakage of private information and enabling secure and encrypted *** primary purpose of steganography is to conceal sensitive information in any form of media such as audio,video,text,or photos,and securely transfer it through wireless *** this paper,we analyse the performance characteristics of one of the steganography techniques called Hidden Communication System for Corrupted Networks(HCCNETs)for hiding sensitive *** performance analysis includes the efficiency and the cost of the system in Wireless Local Area Networks(WLANs),specifically in the IEEE 802.11ah IoT *** analysis is mainly based on a two-dimensional Markov chain model in the presence of an error ***,the model considers packet arrival rate,back-off timer freezing,back-off stages,and short retry limit to ensure compliance with IEEE 802.11ah *** stresses the importance of taking these elements into consideration while modeling the efficiency and cost of the steganographic channel *** parameters often result in a high precise channel access estimation,a more accurate and efficient accuracy measurements system,efficient channel utilisation,avoidance of throughput saturation overestimation,and ensuring that no packet is served *** results demonstrate that HCCNETs is an effective approach at low cost.

关键词： IoT HCCNETs steganography markov chain model

Pulse width modulation voltage source deadtime effect on partial discharge and lifetime of inverter‐fed motor insulation

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High Voltage 2022年第6期7卷 1185-1193页

作者： Shakeel akram Peng Wang Pengfei Meng Gian Carlo Montanari Farhan Hameed Malik College of Electrical Engineering Sichuan UniversityChengduChina Center for Advanced Power Systems Florida State UniversityTallahasseeFloridaUSA Department of Electromechanical Engineering Abu Dhabi PolytechnicAbu DhabiUnited Arab Emirates

This paper analyses the impact of square wave pulse voltage deadtime on the partial discharge(PD)and the lifetime of turn-to-turn insulation.A bipolar repetitive pulse voltage with a deadtime of 0–10μs is produced using double half-bridge solid-state switches having push–pull technology controlled by a field-programmable gate *** mechanism of the discharge process at rising and falling edges of the pulse voltage before and after deadtime is analysed in *** discharge amplitude and PD probability at the rising/falling edges of the voltage waveform increase as the deadtime increases from 0 to 10μs due to the remanent *** number of PD and their intensity is higher at the first rising/falling edges of pulse voltage as compared to the second rising/falling edges for all deadtimes 0–10μ*** the deadtime increases beyond 2μs,the number of PDs increases and concentrates at a specific phase angle of rising/falling *** localise discharges degrade the insulation material and reduce its *** study helps to identify the inverter-fed motor insulation faults due to *** can provide guidelines to motor insulation designers to determine the limit value of deadtime to compensate PD and ensure the safer operation of such motors.

关键词： dead insulation inverter

The role of veterinarians in the One Health approach to antimicrobial resistance perspectives in Jordan

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Animal Diseases 2022年第1期2卷 61-70页

作者： Randa Bazzi akram Alaboudi Gabor Racz Faculty of Public Health University of DebrecenDebrecenHungary Department of Pathology and Public Health Faculty of Veterinary Medicine and SurgeryJordan University of Science and Technology(Retired)Ar-RamthaJordan Department of Public Health and Epidemiology Faculty of MedicineUniversity of DebrecenDebrecenHungary.

This study aims to evaluate the role of Jordanian veterinarians in terms of their knowledge,attitudes and common practices in combating antimicrobial resistance(AMR)and summarize the registered veterinary drugs between *** study data were collected using a standardized questionnaire that focused on the knowledge,attitudes,and practices of Jordanian *** findings were analyzed descriptively;84%of the participants agreed with the statement on the definition of *** majority(95.65%)of participants agreed that AMR is a challenge for the veterinary sector in Jordan and that it should be prioritized over other zoonotic *** 69%of the participants believed that the misuse and overuse of antimicrobials by unqualified,fraudulent,or unauthorized practitioners is the primary reason for the rise of cases associated with AMR and the challenges that accompany *** most common practice among the respondents in this study was to recommend clients(e.g.,farmers and owners)to practice good animal husbandry(80.00%).The study also revealed that there was a significant difference(p=O.015)between attendance at AMR training sessions and the professional sector(private,public,and academic)of the *** study underscores the importance of implementing a continuous education program on AMR so as to enhance the all-round knowledge of veterinarians and improve their advisory *** addition,laws should be enacted to ensure that veterinarians prescribe the correct antimicrobials and to improve surveillance systems for monitoring the use of antimicrobials in veterinary medicine.

关键词： Antimicrobial resistance Veterinarian Knowledge Practices Attitudes Jordan