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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 651-656页

作者： burak ebin Elif Arτg burak zkal Sebahattin Gürmen Metallurgical & Materials Engineering Department Istanbul Technical University

ZnO nanoparticles and porous particles were produced by an ultrasonic spray pyrolysis method using a zinc nitrate precursor at various temperatures under air atmosphere. The effects of reaction temperature on the size and morphology of ZnO particles were investi- gated. The samples were characterized by energy dispersive spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. ZnO particles were obtained in a hexagonal crystal structure and the crystallite shapes changed from spherical to hex- agonal by elevating the reaction temperature. The crystallite size grew by increasing the temperature, in spite of reducing the residence time in the heated zone. ZnO nanoparticles were obtained at the lowest reaction temperature and ZnO porous particles, formed by aggregation of ZnO nanoparticles due to effective sintering, were prepared at higher temperatures. The results showed that the properties of ZnO particles can be controlled by changing the reaction temperature in the ultrasonic spray pyrolysis method.

关键词： zinc oxide nanoparticles nanocrystallites porous materials ultrasonic applications spray pyrolysis

Production of nanocrystalline silver particles by hydrogen reduction of silver nitrate aerosol droplets

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Transactions of Nonferrous Metals Society of China 2013年第3期23卷 841-848页

作者： burak ebin Elif YAZIC I Sebahattin GüRMEN Department of Metallurgical & Materials Engineering Ist anbul Technical University34469IstanbulTurkey

Nanocrystalline silver particles were produced by hydrogen reduction of silver nitrate aerosol droplets formed by high frequency ultrasonic *** dependences of the particle size,morphology and crystallite size on the precursor concentration and the reaction temperature were *** spray pyrolysis process was combined with hydrogen reduction to research the effects on the silver particle *** silver particles including slight oxide structure were prepared at temperature as low as 200 ℃ from silver nitrate under hydrogen atmosphere.X-ray diffraction（XRD） studies showed that pure silver particles were obtained above 200 ℃ reaction *** crystallite sizes of the samples ranged from 29 to 47 *** results indicate that the crystallite sizes hardly ever depended on the reaction *** slightly enlarged by increasing precursor *** observations showed that particles were obtained in spherical morphology with particle sizes between 210 and 525 *** temperature and precursor concentration strongly influenced the particle size.

关键词： silver particles nanocrystalline materials aerosol process hydrogen reduction

Wettability,reactivity,and interface structure in Mg/Ni system

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Journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj P.Darłak J.J.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθ<90°in<1 s),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Exogenous testosterone therapy on choroid in androgen deficiency

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1489-1494页

作者： Volkan Yeter Nurullah Koçak Merve Kalyoncu Ramazan Aşçi Nurşen Aritürk Department of Ophthalmology Ondokuz Mayıs UniversitySamsun 55139Turkey Department of Urology Ondokuz Mayıs UniversitySamsun 55139Turkey

AIM:To investigate the effects of exogenous testosterone treatment on the choroidal parameters in patients with androgen ***:Right eyes of 24 patients with androgen deficiency and 31 healthy volunteers were included in the *** eyes were scanned for subfoveal choroidal thickness(SFCT),choroidal vascularity index(CVI),choroidstromal area(C-SA),choroid-luminal area(C-LA),choroidstromal to luminal area ratio(CSLR),and the choroidal parameters within central 1500μm of the macula(CVI1500,C-LA1500,C-SA1500,and CSLR1500)by enhanced-depth imaging optical coherence tomography(EDI-OCT)at baseline,6th and 18th weeks of the exogenous testosterone ***:The mean SFCT values of the androgen deficient groups and healthy controls were 307.7±27.0 and 303.2±37.2μm(P=0.8).However,CVI,C-SA,CSLR,CVI1500,C-LA1500,and CSLR1500 were significantly different between the groups(all P0.05).However,CVI1500 and LA1500 significantly increased at the end of the follow-up period(Pak are transient in the treatment of patients with androgen ***,the increase in CVI within the central 1500μm of the macula persists even after 4mo.

关键词： testosterone androgen deficiency choroid vascularity index

Assessment of groundwater suitability for different activities in Toshka district,south Egypt

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Journal of Groundwater Science and Engineering 2024年第1期12卷 34-48页

作者： Marwa M Aly Shymaa ak Fayad Ahmed MI Abd Elhamid Faculty of Engineering Mataria Helwan UniversityCairo 11718Egypt Division of Engineering International Academy for Engineering and Media Science(IAEMS)6th of October City 15515Egypt Hydraulics Research Institute National Water Research CenterMWRICairo 13621Egypt

Globally,groundwater has globally emerged as a crucial freshwater source for domestic,irrigation,and industrial *** evaluation of groundwater quality in the Toshka region is imperative to ensure its suitability for the extensive agricultural and industrial activities underway in this promising,groundwater-dependent development *** is particularly significant as Egypt increasingly relies on groundwater reserves to address freshwater deficits and to implement mega-development projects in barren *** this study,fifty-two samples were collected from the recently drilled wells tapping into the Nubian Sandstone Aquifer(NSA)in the Toshka *** quality was assessed through hydrochemical analysis,Piper diagram,and various indicators such as Na%,SAR,RSC,KR,MH and *** hydrochemical analysis revealed improved groundwater quality characteristics,attributed to continuous recharge from Lake *** Piper diagram categorised most of the water samples as"secondary salinity"water *** all wells proved suitable for irrigation with only two wells unsuitable based on MH values and six wells based on KR *** Total Hardness(TH)values,all samples were classified as"Soft",indicating their suitability for domestic and industrial *** Quality Index(WQI)results concluded that all samples met WHO and FAO guidelines for drinking and irrigation,*** distribution maps,constructed using GIS,facilitate the interpretation of the *** monitoring of quality parameters is essential to detect any deviation from permissible limits.

关键词： Nubian Sandstone Aquifer Water Quality Assessment Hydro-chemical Analysis Irrigation Quality Indicators Domestic Use Water Quality Index

All-optical image denoising using a diffractive visual processor

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Light(Science & Applications) 2024年第3期13卷 429-445页

作者： Çağatay Işıl Tianyi Gan Fazil Onuralp Ardic Koray Mentesoglu Jagrit Digani Huseyin Karaca Hanlong Chen Jingxi Li Deniz Mengu Mona Jarrahi Kaan akşit Aydogan Ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos AngelesCA 90095USA California NanoSystems Institute(CNSI) University of CaliforniaLos AngelesCA 90095USA University College London Department of Computer ScienceLondonUnited Kingdom

Image denoising,one of the essential inverse problems,targets to remove noise/artifacts from input *** general,digital image denoising algorithms,executed on computers,present latency due to several iterations implemented in,e.g.,graphics processing units(GPUs).While deep learning-enabled methods can operate non-iteratively,they also introduce latency and impose a significant computational burden,leading to increased power ***,we introduce an analog diffractive image denoiser to all-optically and non-iteratively clean various forms of noise and artifacts from input images–implemented at the speed of light propagation within a thin diffractive visual processor that axially spans<250×λ,whereλis the wavelength of *** all-optical image denoiser comprises passive transmissive layers optimized using deep learning to physically scatter the optical modes that represent various noise features,causing them to miss the output image Field-of-View(FoV)while retaining the object features of *** results show that these diffractive denoisers can efficiently remove salt and pepper noise and image rendering-related spatial artifacts from input phase or intensity images while achieving an output power efficiency of~30–40%.We experimentally demonstrated the effectiveness of this analog denoiser architecture using a 3D-printed diffractive visual processor operating at the terahertz *** to their speed,power-efficiency,and minimal computational overhead,all-optical diffractive denoisers can be transformative for various image display and projection systems,including,e.g.,holographic displays.

关键词： remove rendering holographic

Design and initial testing of a maize cob collection system

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 108-114页

作者： Bojan Dolšak Anita Breznik Klemen Kaučič Nataša Imenšek Marko Marčec Peter Gselman Jani Humar Mitja Krajnc University of Maribor Faculty of Mechanical EngineeringSmetanova ulica 172000 MariborSlovenia ŽIPO Lenart Ltd. Šetarova 212230 LenartSlovenia KGS Krajnc Ltd Vinička vas 42230 LenartSlovenia Interkorn Ltd. Gančani 949231 BeltinciSlovenia

Maize cobs are valuable plant residues that can be used for many different purposes,including as a renewable energy *** their value,maize cobs are still underutilized,mainly because people are not aware of their potential and harvesting techniques for their collection are still being ***,this research focused on finding the most suitable energy-and time-efficient method for mechanical collection of maize *** the combine harvester with an additional hopper proved to be the most promising solution,as it allows harvesting and storage of maize grain and maize cobs in one pass,while the harvesting time remains almost the same and the maize cobs are of good quality,as they do not fall on the field.A prototype with enlarged openings in the straw walkers,an additional grab container for maize cobs,a transport auger,a transport cleaning fan with built-in knives,a transport tube and some other assemblies was fabricated and used in *** first test results are very encouraging(94.4%-96.0%purity of maize cobs)and the system has been patented as a promising solution,especially in times when the environmental sustainability of the planet and energy independence are becoming increasingly important.

关键词： maize cobs utilization mechanical harvesting combine harvester upgrade

Investigation of Fracture Strength of Current Post Materials (Peek, Fiber, Cast Metal) in Different Ferrule Conditions

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Open Journal of Stomatology 2024年第3期14卷 153-172页

作者： Başak Topdaği Funda Bayindir Department of Prosthetic Dentistry Atatürk University Erzurum Türkiye

Aim: The fracture resistance of the post materials used nowadays significantly impacts the fracture type of the post material. The current study aimed to examine the impact of the fracture resistance of PEEK posts, whose use as a post material has not yet become widespread, on the fracture pattern that will occur. Materials and Methods: Sixty-six extracted upper central incisor human teeth were used in the study. Six groups of posts were produced from metal, fiber, and PEEK materials (n = 11). Afterward, the fracture resistance test was applied to the samples. Samples were classified according to fracture type as repairable or irreparable. The ANOVA and test were used in statistical analysis. Post-hoc tests were carried out using Tukey’s and Tamhane’s T2 tests. On the other hand, Pearson’s chi-square test and the Fisher-Freeman-Halton test were conducted for comparisons between categorical variables. The statistical significance level was accepted as p Results: According to the fracture resistance test results, the groups where metal personal posts were used displayed higher fracture resistance in comparison with all other groups. According to the results of the optical microscope examination, the incidence of repairable fractures was significantly higher in the PEEK post group with ferrule preparation (p 0.05). Conclusion: In the absence of the ferrule effect, fractures are catastrophic, regardless of the material used. The use of PEEK as a post material contributes to keeping fractures at a repairable level.

关键词： Component Formatting Style Styling Insert

适用于MMC-MTDC的母线侧故障分析及保护策略

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高电压技术 2024年第5期50卷 2067-2077,I0019-I0022页

作者：鄢仁武俞智鹏方略斌福建理工大学电子电气与物理学院福州350118 智能电网仿真分析与综合控制福建省高校工程研究中心福州350118 国网福建省电力有限公司福州350013

柔性直流输电系统中,直流故障的分析与判别是柔直系统中亟待解决的重要问题。为了更好地分析故障特征,推导出一种多端柔性直流输电网(modular multilevel converter-high voltage direct current,MMC-MTDC)的母线侧简化电路故障计算方法... 详细信息

柔性直流输电系统中,直流故障的分析与判别是柔直系统中亟待解决的重要问题。为了更好地分析故障特征,推导出一种多端柔性直流输电网(modular multilevel converter-high voltage direct current,MMC-MTDC)的母线侧简化电路故障计算方法,并分析了母线侧单极接地故障和极间短路故障的故障特征,在此基础上设计了一种适用于多端柔性直流输电网的故障判别方案和保护措施。该判别方案通过故障启动判据、故障区域判别和故障类型判别3个模块进行故障判定,采用了故障电压瞬时跌落值与系统电压之差及故障线路电流值作故障特征量,整套判别方案不受其他元件参数、故障位置等因素的影响,将Spearman相关性分析与传统电气故障区域判别相结合,准确判定系统区内外故障的同时,解决了故障区域判别中受线路各参数干扰导致误判的问题,仿真测试验证了本保护方案的可行性。

关键词： MMC-HVDC 直流故障母线侧故障故障特征 Spearman相关性分析保护设计

Levels of evidence and grades of recommendation supporting European society for medical oncology clinical practice guidelines

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Oncology Research 2024年第5期32卷 807-815页

作者： MARKO SKELIN BRUNA PERKOV-STIPIČIN SANJA VUŠKOVIĆ MARINAŠANDRK PLEHAČEK ANE BAŠIĆ DAVIDŠARČEVIĆ MAJA ILIĆ IVAN KREČak Pharmacy Department General Hospital ofŠibenik-Knin CountyŠibenikCroatia Faculty of Medicine University of RijekaRijekaCroatia Undergraduate Study in Nursing University of Applied SciencesŠibenikCroatia Department of Oncology University Hospital Center ZagrebZagrebCroatia Pharmacies Joukhadar Sveta NedeljaCroatia Pharmacies Prima Pharme ZagrebCroatia Pharmacy Department General Hospital ZadarZadarCroatia Pharmacy Department General Hospital PulaPulaCroatia Department of Internal Medicine General Hospital ofŠibenik-Knin CountyŠibenikCroatia

Background:The European Society for Medical Oncology(ESMO)guidelines are among the most comprehensive and widely used clinical practice guidelines(CPGs)***,the level of scientific evidence supporting ESMO CPG recommendations has not been systematically *** study assessed ESMO CPG levels of evidence(LOE)and grades of recommendations(GOR),as well as their trends over time across various cancer ***:We manually extracted every recommendation with the Infectious Diseases Society of America(IDSA)classification from each *** examined the distribution of LOE and GOR in all available ESMO CPG guidelines across different topics and cancer ***:Among the 1,823 recommendations in the current CPG,30%were classified as LOEⅠ,and 43%were classified as GOR ***,there was a slight decrease in LOEⅠ(−2%)and an increase in the proportion of GOR A(+1%)in the current CPG compared to previous *** proportion of GOR A recommendations based on higher levels of evidence such as randomized trials(LOEⅠ–Ⅱ)shows a decrease(71%vs.63%,p=0.009)while recommendations based on lower levels of evidence(LOEⅢ–Ⅴ)show an increase(29%vs.37%,p=0.01)between previous and current *** the current versions,the highest proportion of LOEⅠ(42%)was found in recommendations related to pharmacotherapy,while the highest proportion of GOR A recommendations was found in the areas of pathology(50%)and diagnostic(50%)*** variability in LOEⅠand GOR A recommendations and their changes over time was observed across different cancer ***:One-third of the current ESMO CPG recommendations are supported by the highest level of *** well-designed randomized clinical trials are needed to increase the proportion of LOEⅠand GOR A recommendations,ultimately leading to improved outcomes for cancer patients.

关键词： ESMO guidelines Clinical practice guidelines Level of evidence Grade of recommendation