检索结果-内蒙古大学图书馆

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.Castro-Lopes J.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

来源：评论

学校读者我要写书评

暂无评论

Surface modification techniques of membranes to improve their antifouling characteristics:recent advancements and developments

引用

Frontiers of Chemical Science and engineering 2023年第12期17卷 1837-1865页

作者： Muhammad Tawalbeh Haya Aljaghoub Muhammad Qasim Amani Al-Othman Sustainable and Renewable Energy Engineering Department University of SharjahSharjah 27272United Arab Emirates Sustainable Energy&Power Systems Research Centre RISEUniversity of SharjahSharjah 27272United Arab Emirates Industrial Engineering and Engineering Management Department University of SharjahSharjah 27272United Arab Emirates Department of Chemical and Biological Engineering American University of SharjahSharjah 26666United Arab Emirates Materials Science and Engineering Program College of Arts and SciencesAmerican University of SharjahSharjah 26666United Arab Emirates

Extensive research efforts are currently devoted to developing and improving conventional technologies for water treatment. Membrane-based water treatment technologies are among the most preferred options due to their commercial success, simple operation, low energy and space requirements, and high separation efficiency. Despite the advances made in membrane-based technologies, fouling remains a critical challenge. Fouling occurs upon the accumulation of unwanted impurities on the membrane surface and within the membrane pores which results in a significant decline in the membrane permeate flux. To alleviate the operational challenges from fouling, surface modification to develop antifouling membranes appears to be an effective technique. A comprehensive review of the surface modification techniques for the development of antifouling membranes is provided in this paper. Chemical surface modification techniques (grafting and plasma treatment), physical modification techniques (blending, coating, adsorption, and thermal treatment), and combined physical and chemical modification techniques have been discussed. Moreover, the challenges related to surface modification and the future research directions are addressed.

关键词： fouling antifouling membrane surface modification membrane pretreatment

来源：评论

学校读者我要写书评

暂无评论

Tributyrin is more effective than tripropionin in reducing plasma cholesterol in hypercholesterolemic hamsters

引用

Food Science and Human Wellness 2024年

作者： Shouhe Huang Chi Yan Huafang Ding Zixing Chen Hanyue Zhu Wensen He Lin Lei Zhen-Yu Chen Food and Nutritional Sciences Program， School of Life Sciences， Faculty of Science， The Chinese University of Hong Kong School of Food Science and Engineering/Guangdong Provincial Key Laboratory of Intelligent Food Manufacturing， Foshan University School of Food and Biological Engineering， Jiangsu University College of Food Science， Southwest University

Propionate and butyrate are proven capable of decreasing plasma cholesterol. However， their undesired odor and unpleasant smell limit their direct application as a dietary supplement. In contrast， their respective triacylglycerols tributyrin (Tb) and tripropionin (Tp) are odorless and can be directly used as healthy supplements. In view that no study has investigated the relative biological potency of Tb and Tp， the present study was designed to compare the effects of Tp and Tb on plasma cholesterol and gut microbiota using hypercholesterolemic hamsters as a model. Male golden hamsters were randomly allocated to 6 groups fed one of the following six diets， namely， low-cholesterol diet (LCD)， high-cholesterol diet (HCD)， HCD + 0.5% Tp (LTp)， HCD + 1%Tp (HTp)， HCD + 0.5%Tb (LTb)， and HCD + 1%Tb (HTb). Results showed that Tb administration at 1% could significantly reduce plasma TC， non-HDL-C， and the ratio of non-HDL-C to HDL-C， whereas Tp supplementation had no effect. Mechanistically， Tb but not Tp could decrease plasma cholesterol by increasing the excretion of fecal bile acids via upregulating gene expression of CYP7A1 and LXRα. In addition， Tb supplementation at 1% could increase the gut microbiota diversity， reduce the ratio of Firmicutes/Bacteroidetes and favorably increase the abundance of beneficial microbial genera Bifidobacterium. In conclusion， dietary Tb supplementation was more effective than Tp in mitigating hypercholesterolemia by increasing the excretion of fecal bile acids and favorably modulating gut microbiota.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Modelling the development of biological structures displaying longitudinal geometries in vitro:culturing pluripotent stem cells on plasma-treated,growth factor-coupled polycaprolactone fibres

引用

Engineered Regeneration 2024年第1期5卷 124-138页

作者： Badwi B.Boumelhem Stuart T.Fraser Syamak Farajikhah Rachel A.Shparberg Michael B.Morris Marcela M.M.Bilek Anyu Zhang Behnam Akhavan Simon Fleming Maryanne Large School of Physics Faculty of ScienceUniversity of SydneyAustralia Sydney Nano Institute University of SydneyAustralia School of Chemical and Biomolecular Engineering University of SydneyAustralia School of Medical Sciences Faculty of Medicine and HealthUniversity of SydneyAustralia School of Biomedical Engineering Faculty of EngineeringUniversity of SydneyAustralia School of Engineering University of NewcastleCallaghanNSW 2308Australia Hunter Medical Research Institute(HMRI) Precision Medicine ProgramNew Lambton Heights NSW 2305Australia

Many biological structures such as nerves,blood and lymphatic vessels,and muscle fibres exhibit longitudinal ge-ometries with distinct cell types extending along both the length and width of internal linear *** these three-dimensional structures in vitro is challenging:the best-defined stem-cell differentiation systems are mono-layer cultures or organoids using pluripotent stem *** stem cells can differentiate into functionally mature cells depending on the signals received,holding great promise for regenerative ***,the integration of in vitro differentiated cell types into diseased tissue remains a *** scaffolds can bridge this gap if the appropriate signalling systems are incorporated into the ***,we have taken a biomimicry approach to generate longitudinal structures in *** this approach,mouse embryonic stem cells are directed to differentiate to specific cell types on the surface of polycaprolactone(PCL)fibres treated by plasma-immersion ion implantation and to which with lineage-specifying molecules have been covalently *** demonstrate the simplicity and utility of our method for efficiently generating high yields of the following cell types from these pluripotent stem cells:neurons,vascular endothelial cells,osteoclasts,adipocytes,and cells of the erythroid,myeloid,and lymphoid *** arranged plasma-treated scaffolds with differentiated cell types could ultimately serve as a means for the repair or treatment of diseased or damaged tissue.

关键词： Pluripotent stem cells Lineage commitment Growth factors Biomaterial engineering Plasma-immersion ion implantation Covalent biomolecule attachment Polycaprolactone

来源：评论

学校读者我要写书评

暂无评论

Comparison between different internal cross-sections for pulmonary secretion suction catheters

引用

Research on Biomedical engineering 2022年第3期38卷 965-975页

作者： dos Santos Lima, Bruna Luiza Tadeu Las Casas, Marina Spyer de Oliveira, Patrícia Muniz Huebner, Rudolf Rodrigues-Machado, Maria da Glória de Las Casas, Estevam Barbosa Department of Structural Engineering Federal University of Minas Gerais Belo Horizonte Brazil Department of Mechanical Engineering Federal University of Minas Gerais Belo Horizonte Brazil Faculty of Medical Sciences of Minas Gerais Post-graduate Program in Health Sciences Belo Horizonte Brazil

Introduction: Endotracheal suctioning is a procedure to remove pulmonary secretions, which can lead to complications such as hypoxemia. To minimize this risk, a double-lumen pulmonary secretion suction device was developed at the Biomechanics Laboratory of the University of Minas Gerais. The aim of the study is to evaluate the flow of the removal of pulmonary secretions by reducing the cross-section for the passage of mucus, considering catheters with three new, distinct internal cross-sections (circular, semicircular, and curved). Methods: The study was divided into two stages: computer simulations in the software Ansys Fluent using three new internal cross-sections in order to assess the flow rate, secretion removal, and the preparation of solutions of mucus simulators (polyethylene glycol) in three concentrations (semi-liquid, intermediate, and semi-solid) to be aspirated by 12 Fr catheters and by a printed circular catheter in the bench test. Results: It was verified in a bench test that the relationship between shear stress and deformation rate of mucus simulator solutions is not linear and that a suction pressure of less than 300 mmHg, performed by a standard catheter, generates moderate rates of removal of thicker solutions. It is possible to verify, by computer simulations, higher flow rate levels when reducing the length of the circular catheter from 0.5 to 0.4 m. Semicircular catheter produces high flow rates when compared to other proposed catheters. Conclusion: Based on the results obtained, a dual-lumen semicircular catheter can be designed and validated by computer simulation. © 2022, Sociedade Brasileira de Engenharia Biomedica.

关键词： Catheters

来源：评论

学校读者我要写书评

暂无评论

One-Step to Prepare Lignin Based Fluorescent Nanoparticles with Excellent Radical Scavenging Activity

引用

Journal of Renewable Materials 2024年第5期12卷 895-908页

作者： Xujing Zhang Hatem Abushammala Debora Puglia Binbao Lu Pengwu Xu Weijun Yang Piming Ma The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi214122China Environmental Health and Safety Program College of Health SciencesAbu Dhabi UniversityP.O.Box 59911Abu DhabiUnited Arab Emirates Civil and Environmental Engineering Department Materials Engineering CenterPerugia UniversityUdR INSTMTerni05100Italy

Fluorescent nanomaterials have attracted much attention,due to their unique luminescent properties and promis-ing applications in biomedical *** this study,lignin basedﬂuorescent nanoparticles(LFNP)with high yield(up to 32.4%)were prepared from lignin nanoparticles(LNP)by one-pot hydrothermal method with ethylene-diamine(EDA)and citric *** and chemical structure of LFNP were investigated by SEM,FT-IR,and zeta potential,and it was found that the structure of LFNP changed with the increase of citric acid *** showed the highestﬂuorescence intensity under UV excitation at wavelengths of 375–385 nm,with emis-sion wavelengths between 454–465 nm,and exhibited strong photoluminescence ***,with the increase of citric acid content,the energy gap(ΔE)gradually decreased from 3.87 to 3.14 eV,which corresponds to the gradual enhancement ofﬂuorescence *** also exhibited excellent antioxidant activity,with DPPH free radical scavenging rate increased from 80.8%for LNP up to 96.7%for LFNP,conﬁrming the great potential of these materials for application in biomedicine and cosmetic health care.

关键词： Lignin ﬂuorescent nanoparticles bioactivity photoluminescence mechanism

来源：评论

学校读者我要写书评

暂无评论

Fast non-iterative algorithm for 3D point-cloud holography

引用

Optics Express 2023年第22期31卷 36468-36485页

作者： Ersaro, Nathan Tessema Yalcin, Cem Murray, Liz Kabuli, Leyla Waller, Laura Muller, Rikky Graduate Program in Bioengineering University of California Berkeley and University of California San Francisco BerkeleyCA94720 United States Department of Electrical Engineering and Computer Sciences University of California Berkeley BerkeleyCA94720 United States

Recently developed iterative and deep learning-based approaches to computer-generated holography (CGH) have been shown to achieve high-quality photorealistic 3D images with spatial light modulators. However, such approaches remain overly cumbersome for patterning sparse collections of target points across a photoresponsive volume in applications including biological microscopy and material processing. Specifically, in addition to requiring heavy computation that cannot accommodate real-time operation in mobile or hardware-light settings, existing sampling-dependent 3D CGH methods preclude the ability to place target points with arbitrary precision, limiting accessible depths to a handful of planes. Accordingly, we present a non-iterative point cloud holography algorithm that employs fast deterministic calculations in order to efficiently allocate patches of SLM pixels to different target points in the 3D volume and spread the patterning of all points across multiple time frames. Compared to a matched-performance implementation of the iterative Gerchberg-Saxton algorithm, our algorithm’s relative computation speed advantage was found to increase with SLM pixel count, reaching >100,000x at 512 × 512 array format. © 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Iterative methods

来源：评论

学校读者我要写书评

暂无评论

The effect of Zn2+ ion substitution on nanoparticles of ZnxMn(1-X) Fe2O4 (X = 0.2, 0.4, 0.6, 0.8) towards signal surface plasmon resonance (SPR)

引用

Materials Research Innovations 2023年第6期27卷 420-428页

作者： Almi Putra, Rachmad Andi Fadlly, Teuku Asmara, Vina Monica, Desy Sartika Hijrahnisa Novia, Wina Yakob, Muhammad Indrayana, Ipt Geubrina Raszky, Rachmita Mujahid Hamdan, Abd Arfi, Febrina Rahwanto, Adi Jalil, Zulkarnain Physics Study Program Faculty of Engineering Universitas Samudra Langsa Indonesia Doctoral Study Program School of Engineering Universitas Syiah Kuala Banda Aceh Indonesia Department of Physics Education Faculty of Teaching and Education Universitas Samudra Langsa Indonesia Physics Study Program Faculty of Natural Science and Engineering Technology Universitas Udayana Denpasar Indonesia Department of Environmental Engineering Faculty of Science and Technology UIN Ar-Raniry Banda Aceh Indonesia Department of Chemistry Faculty of Science and Technology UIN Ar-Raniry Banda Aceh Indonesia Department of Physics Faculty of Mathematics and Natural Sciences Syiah Kuala University Banda Aceh Indonesia

This study examined the effect of Zn2+ ion substitution on ZnxMn(1-x) Fe2O4 nanoparticles (x = 0.2, 0.4, 0.6, 0.8) towards signal Surface Plasmon Resonance (SPR). The co-precipitation method synthesised the nanoparticles at a temperature of 90°C. The X-Ray Diffraction (XRD) results showed a polycrystalline structure with a crystallite size varied from 19.05 nm to 19.77 nm. In addition, as the Zn element increased in the ZnxMn(1-x)Fe2O4 nanoparticles, the degree of crystallinity increased by 21.72%, respectively. The optical properties of the nanoparticles ZnxMn(1-x) Fe2O4 indicate absorbance at wavelengths of 330.36–331.74 nm. The absorbance level increased as the Zn element decreased, resulting a direct optical gap of 3.47 eV and an indirect optical gap of 3.23 eV. The Attenuated Total Reflection (ATR) curve in the SPR biosensor indicated a shift in the reflective angle of the Prism/Au/Air configuration, which is 47.78° on Prisma/Au/nanoparticle of Zn0.8Mn0.2Fe2O4/air by 50.75°, and the prism/Au/nanoparticle of Zn0.2Mn0.8Fe2 O4/air by 51.04°. The substitution of Zn ions in the compound Zn x Mn(1-x)Fe2O4 affects the resulting ATR curve. The shift in the SPR angle is caused by changes in the refractive index in each layer which is influenced by the concentration of each material which has an impact on the absorbance ability and photon reflectance. This research has the potential to continue with the testing of dielectric and magnetic properties, as well as special testing for biological analytes compatible with ZnxMn(1-x)Fe2O4 nanoparticles. © 2023 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Surface plasmon resonance

来源：评论

学校读者我要写书评

暂无评论

Web Portal Validation Model by Digital Signature and ISO 27002 to Reduce Private Credentials Theft for Phishing Attacks to Financial Sector Customers

Web Portal Validation Model by Digital Signature and ISO 270...

引用

Electrical, Computer and Energy Technologies (ICECET), International Conference on

作者： Jose Villanueva Jorge Sebastian Jymmy Dextre Systems Engineering Program Peruvian University of Applied Sciences Lima Peru

ISBN: (数字)9798350395914

ISBN: (纸本)9798350395921

Phishing attacks increase by 46% since 2018, mainly affecting the financial sector with losses on average of $3.66 million during 2019. The poor validation procedures of legitimate websites and the carefree aptitude of users in the face of this type of attack have generated their proliferation. The proposed model is divided into the phases of analysis, design, development, experimentation and monitoring; in which the necessary tools are selected, the system architecture is designed considering the criteria of effectiveness, performance, functionality, security and perception of usefulness; It is developed in three layers: backend, middleware, and frontend. The data transfer between the layers implemented the concepts of digital signature in the use of the hash algorithm, asymmetric key and QR codes updated at time intervals. The validation process was carried out using a sample of 106 active users of financial institutions, 100 QR codes, 7 stress loads and in accordance with the ISO 27002 standard. The model reduced the theft of confidential information by 88.87% in an interval of 3 to 6 seconds in the validation process with 100% effectiveness. Likewise, it obtained a 100% satisfaction rate and risk management according to ISO 27002 covered the main inherent risks related to sniffing, QR code spoofing, unauthorized access, cessation of operations and increased latency in the validation process.

关键词： ISO Standards Phishing Web pages Systems architecture QR codes Time measurement Web sites Digital signatures Stress Standards

来源：评论

学校读者我要写书评

暂无评论

Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

引用

Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi Yu Faith Teo En Ning Chang Liu Yu-Chi Liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：