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烧结温度对La_(0.6)Ca_(0.4)mnO_3结构、磁性和磁致热效应的影响(英文)

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Transactions of Nonferrous metals society of China 2014年第S1期24卷 141-145页

作者： seung Rok LEE m.s.anwar Faheem AHmED Bon Heun KOO school of materials science and Engineering Changwon National University

研究了烧结温度对La0.6Ca0.4mnO3的结构、磁转变和磁熵的影响。观察表明,该化合物属于具有Pnma空间群的斜方晶系结构,不含任何杂质。研究烧结温度对居里温度(TC)的影响,发现提高烧结温度,TC稍有增大。磁致热效应研究显示,随着烧结温度... 详细信息

研究了烧结温度对La0.6Ca0.4mnO3的结构、磁转变和磁熵的影响。观察表明,该化合物属于具有Pnma空间群的斜方晶系结构,不含任何杂质。研究烧结温度对居里温度(TC)的影响,发现提高烧结温度,TC稍有增大。磁致热效应研究显示,随着烧结温度的变化,磁熵会发生显著的变化。在外加磁场为3 T、烧结温度为1300°C时,相对冷却能(RCP)为89 J/kg。因此,该化合物可以考虑作为在室温附近或低于室温的潜在磁制冷材料。

关键词：亚锰酸盐磁热效应烧结温度巨磁阻

单晶金红石型TiO_2纳米棒的湿法合成(英文)

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Transactions of Nonferrous metals society of China 2014年第S1期24卷 152-156页

作者： Rehan DANIsH Faheem AHmED Nishat ARsHI m.s.anwar Bon Heun KOO school of Nano and Advanced materials Engineering Changwon National University

用TiO2粉末、NaOH和蒸馏水为原料合成金红石型TiO2纳米棒。XRD和FEsEm分析表明,制备的样品为单晶且无杂质,其平均粒径约为40 nm。当样品于600°C退火2 h后,FEsEm观察发现生成了TiO2纳米棒。XRD分析表明纳米棒为单晶。纳米棒表面光滑,其... 详细信息

用TiO2粉末、NaOH和蒸馏水为原料合成金红石型TiO2纳米棒。XRD和FEsEm分析表明,制备的样品为单晶且无杂质,其平均粒径约为40 nm。当样品于600°C退火2 h后,FEsEm观察发现生成了TiO2纳米棒。XRD分析表明纳米棒为单晶。纳米棒表面光滑,其长约为1μm,直径约为80 nm。紫外和拉曼光谱研究表明,所制备样品的能带间隙为3.40 eV。

关键词： TiO2 纳米棒湿法晶粒生长金红石

Treadmill training in Parkinson's disease:possible role of prefrontal modifications in the improved cortical-subcortical network function

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Neural Regeneration Research 2024年第2期19卷 407-408页

作者： Hao Ding Amgad Droby Abdul Rauf anwar Jeffrey m.Hausdorff Bahman Nasseroleslami Anat mirelman Inbal maidan muthuraman muthuraman Department of Neurology University Hospital WürzburgWürzburgGermany Academic Unit of Neurology Trinity College Dublinthe University of DublinDublinIreland Department of Neurology Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael sagol school of Neuroscience Tel Aviv UniversityTel AvivIsrael Biomedical Engineering Centre UET Lahore(KSK Campus)LahorePakistan Laboratory for Early markers of Neurodegeneration(LEmON) Center for the Study of MovementCognitionand Mobility(CMCM)Neurological InstituteTel Aviv Sourasky Medical CenterTel AvivIsrael Department of Physical Therapy Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael Rush Alzheimer’s Disease Center and Department of Orthopaedic surgery Rush University Medical CenterChicagoILUSA

Parkinson’s disease(PD)is a complex neurodegenerative disorder characterized by a range of motor symptoms such as bradykinesia,resting tremor,rigidity,and postural instability,as well as non-motor symptoms,such as de... 详细信息

关键词： rigidity fatigue

Ultrahydrophobic melamine sponge via interfacial modification with reduced graphene oxide/titanium dioxide nanocomposite and polydimethylsiloxane for oily wastewater treatment

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Water science and Engineering 2024年第2期17卷 139-149页

作者： Hamidatu Alhassan Ying Woan soon anwar Usman Voo Nyuk Yoong Department of Physics Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei Department of Chemical sciences Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei

Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and elasticity.Given their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of applications.In this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(ms)through interfacial modification using a solution immersion technique.To further modify it,poly-dimethylsiloxane(PDms)was grafted onto its surface to establish stronger covalent bonds with the composite.The water contact angle of the sponge(rGO/TiO_(2)/PDms/ms)was 164.2°,which satisfies the condition for ultrahydrophobicity.The evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf effect.As a result of the increased density of rGO/TiO_(2)/PDms/ms,it recorded an initial capacity that was 2 g/g lower than the raw ms for crude oil absorption.The raw ms retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDms/ms retained 97%,suggesting good recyclability.Excellent oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDms/ms in oil-water combinations.In a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.

关键词： Oily wastewater Reduced graphene oxide Polydimethylsiloxane(PDms) Emulsion separation melamine sponge

Cost-Efficient medium Frequency Propagation Research with software Defined Radio

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World Journal of Engineering and Technology 2024年第1期12卷 158-169页

作者： Casey m. Hess sohail anwar Division of Business Engineering and Information Sciences and Technology Department of Electromechanical Engineering Technology Pennsylvania State University Altoona Campus Altoona Pennsylvania USA Division of Business Engineering and Information Sciences and Technology Department of Engineering Pennsylvania State University Altoona Campus Altoona Pennsylvania USA

medium Frequency radio holds significance in modern society as it supports broadcasting and individual communications in the public, government, and military sectors. Enhancing the availability and quality of these communications is only possible by enhancing the understanding of medium frequency propagation. While traditional methods of radio wave propagation research can have a high material demand and cost, software defined radio presents itself as a versatile and low-cost platform for medium frequency signal reception and data acquisition. This paper details a research effort that utilizes software defined radio to help characterize medium frequency signal strength in relation to ionospheric and solar weather propagation determinants. signal strength data from seven medium frequency stations of unique transmission locations and varying transmission powers were retrieved in 24-hour segments via a receiving loop antenna, Airspy HF+ Discovery software defined radio, and sDR sharp software interface network. Retrieved data sets were visualized and analyzed in mATLAB for the identification of signal strength trends, which were subsequently compared to historical ionospheric and space weather indices in pursuit of a quantifiable correlation between such indices and medium frequency signal strengths. The results of the investigation prove that software defined radio, when used in conjunction with a receiving antenna and data analysis program, provides a versatile mechanism for cost-efficient propagation research.

关键词： Ionosphere space Weather Airspy sDR sDR sharp mATLAB Analysis

survey of Indoor Localization Based on Deep Learning

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Computers, materials & Continua 2024年第5期79卷 3261-3298页

作者： Khaldon Azzam Kordi mardeni Roslee mohamad Yusoff Alias Abdulraqeb Alhammadi Athar Waseem anwar Faizd Osman Centre for Wireless Technology Faculty of EngineeringMultimedia UniversityCyberjaya63100Malaysia Communication systems&Networks Research Lab Malaysia-Japan International Institute of TechnologyUniversiti Teknologi MalaysiaKuala Lumpur54100Malaysia Department of Electrical Engineering(DEE) International Islamic UniversityIslamabad44000Pakistan Rohde&schwarz(m)sdn Bhd Shah Alam40150Malaysia

This study comprehensively examines the current state of deep learning (DL) usage in indoor positioning.It emphasizes the significance and efficiency of convolutional neural networks (CNNs) and recurrent neuralnetworks (RNNs). Unlike prior studies focused on single sensor modalities like Wi-Fi or Bluetooth, this researchexplores the integration of multiple sensor modalities (e.g.,Wi-Fi, Bluetooth, Ultra-Wideband, ZigBee) to expandindoor localization methods, particularly in obstructed environments. It addresses the challenge of precise objectlocalization, introducing a novel hybrid DL approach using received signal information (RsI), Received signalstrength (Rss), and Channel state Information (CsI) data to enhance accuracy and stability. moreover, thestudy introduces a device-free indoor localization algorithm, offering a significant advancement with potentialobject or individual tracking applications. It recognizes the increasing importance of indoor positioning forlocation-based services. It anticipates future developments while acknowledging challenges such as multipathinterference, noise, data standardization, and scarcity of labeled data. This research contributes significantly toindoor localization technology, offering adaptability, device independence, and multifaceted DL-based solutionsfor real-world challenges and future advancements. Thus, the proposed work addresses challenges in objectlocalization precision and introduces a novel hybrid deep learning approach, contributing to advancing locationcentricservices.While deep learning-based indoor localization techniques have improved accuracy, challenges likedata noise, standardization, and availability of training data persist. However, ongoing developments are expectedto enhance indoor positioning systems to meet real-world demands.

关键词： Deep learning indoor localization wireless-based localization

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), L

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

Influence of cerium ions on structure-dependent magnetic properties of Ba-sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar sunil m.Patange P.m.Dighe sher singh meena Abdullah GAl-sehemi mehboobali Pannipara santosh s.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia solid state Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPs data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FEsEm profiles of the ferrite samples.The magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.s.m,and mossbauer spectroscopy,respectively.The hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-sr hexaferrite Ce^(3+)substitution XPs saturation magnetization Coercivity m?ssbauer spectroscopy

Adult neurogenesis:a real hope or a delusion?

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Neural Regeneration Research 2024年第1期19卷 6-15页

作者： Ghulam Hussain Rabia Akram Haseeb anwar Faiqa sajid Tehreem Iman Hyung soo Han Chand Raza Jose-Luis Gonzalez De Aguilar Neurochemicalbiology and Genetics Laboratory(NGL) Department of PhysiologyFaculty of Life SciencesGovernment College UniversityFaisalabadPunjabPakistan Department of Physiology School of MedicineClinical Omics InstituteKyungpook National UniversityDaeguKorea Department of Zoology Faculty of Chemistry and Life SciencesGovernment College UniversityLahorePakistan INsERm U1118Mécanismes Centraux et Péripheriques de la NeurodégénérescenceStrasbourgFranceUniversitéde StrasbourgStrasbourgFrance

Adult neurogenesis,the process of creating new neurons,involves the coordinated division,migration,and differentiation of neural stem cells.This process is restricted to neurogenic niches located in two distinct areas of the brain:the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle,where new neurons are generated and then migrate to the olfactory bulb.Neurogenesis has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem cells.Interestingly,recent years have seen tremendous progress in our understanding of adult brain neurogenesis,bridging the knowledge gap between embryonic and adult neurogenesis.Here,we discuss the current status of adult brain neurogenesis in light of what we know about neural stem cells.In this notion,we talk about the importance of intra cellular signaling molecules in mobilizing endogenous neural stem cell prolife ration.Based on the current understanding,we can declare that these molecules play a role in targeting neurogenesis in the mature brain.However,to achieve this goal,we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints,which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.

关键词： adult neurogenesis aging brain-derived neurotrophic factor dentate gyrus hippocampus neural stem cells neurotrophic factors Notch oxidative stress stem cells subgranular zone