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Energy transfer and luminescent properties of Tb^(3+)and Tb^(3+),Yb^(3+)doped cNGG phosphors

Journal of Rare Earths 2022年第9期40卷 1445-1453,I0004页

作者： S.Hau G.Stanciu D.avram L.Gheorghe c.Gheorghe National Institute for Laser Plasma and Radiation PhysicsSolid State Quantum Electronics Laboratory409 Atomistilor StreetP.O.Box MG-36Magurele077125IlfovRomania

In this work,calcium niobium gallium garnet(ca_(3)Nb_(1.6875)Ga_(3.1875)O_(12)-cNGG)ceramic samples singledoped with Tb^(3+)and co-doped with Tb^(3+)and Yb^(3+)ions were sintered by the solid-state reaction *** structural characterization of the samples was carried out by X-ray diffraction *** optimal concentration of Tb^(3+)ions corresponding to the maximum luminescence in the green spectral range in cNGG:x at%Tb(x=0.1,0.5,1,2,3,4,and 5)was determined to be 4 at%.The timeresolved luminescence of the^(5)D_(4)level(Tb^(3+))in the cNGG:x at%Tb samples was analysed to explore the quenching mechanisms involved in the Tb^(3+)green ***-doped cNGG:4 at%Tb,y at%Yb(y=0.5,2,4,6,8,and 10)ceramics were prepared and *** is shown that cNGG:4 at%Tb,y at%Yb phosphors exhibit intense green luminescence under ultra-violet(UV),visible(VIS),and near-infrared(NIR)excitation,thus demonstrating the presence of simultaneous down-conversion(Dc)and upconversion(Uc)*** dependence of the Uc luminescence intensity on the diode laser pumping power was measured and the results indicate a two-photon process based on cooperative energy transfer(cET).Under UV excitation,the lifetime of the^(5)D_(4)(Tb^(3+))level slowly increases with increase of Yb^(3+)concentration,suggesting the energy transfer from Yb^(3+)to Tb^(3+)ions,while under NIR excitation,the lifetime of the^(5)D_(4)(Tb^(3+))level decreases with increase of Yb^(3+)ions concentration,indicating the presence of a strong energy transfer from Tb^(3+)to Yb^(3+)*** highest energy transfer efficiency ofη_(ET)≈42%was determined for the cNGG:4 at%Tb,10 at%Yb *** obtained results indicate that cNGG:(Tb^(3+),Yb^(3+))could be efficient new yellowish-green-emitting phosphors.

关键词： Phosphors Tb^(3+)and Tb^(3+)-Yb^(3+)luminescence properties Up-conversion Down-conversion Quantum cutting process Rare earths

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System-level Pareto frontiers for on-chip thermoelectric coolers

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Frontiers in Energy 2018年第1期12卷 109-120页

作者： Sevket U. YURUKER Michael c. FISH Zhi YANG Nicholas BALDASARO Philip barLETTA avram bar-c.hen Bao YANG Department of Mechanical Engineering University of MarylandCollege Park MD 20742 USA Research Triangle Institute Research Triangle Park NC 27709 USA Micross components Research Triangle Park NC 27709 USA

The continuous rise in heat dissipation of integrated circuits necessitates advanced thermal solutions to ensure system reliability and efficiency. Thermoelectric coolers are among the most promising techniques for dealing with localized on-chip hot spots. This study focuses on establishing a holistic optimization methodol- ogy for such thermoelectric coolers, in which a thermo- electric element＇s thickness and the electrical current are optimized to minimize source temperature with respect to ambient, when the thermal and electrical parasitic effects are considered. It is found that when element thickness and electrical current are optimized for a given system architecture, a ＂heat flux vs. temperature difference＂ Pareto frontier curve is obtained, indicating that there is an optimum thickness and a corresponding optimum current that maximize the achievable temperature reduc- tion while removing a particular heat flux. This methodol- ogy also provides the possible system level AT＇s that can be achieved for a range of heat fluxes, defining the upper limits of thermoelectric cooling for that architecture. In this study, use was made of an extensive analytical model, which was verified using commercially available finite element analysis software. Through the optimization process, 3 pairs of master curves were generated, which were then used to compose the Pareto frontier for any given system architecture. Finally, a case study wasperformed to provide an in-depth demonstration of the optimization procedure for an example application.

关键词： thermoelectric cooling thermal management,optimization high flux electronics

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Route Towards Road Freight Electrification in India:Examining Battery Electric Truck Powertrain and Energy consumption

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chinese Journal of Electrical Engineering 2022年第3期8卷 57-75页

作者： Sreedhar Madichetty avram John Neroth Sukumar Mishra B.chitti Babu Department of Electrical and Electronics Engineering Mahindra University Ecole CentraleHyderabad 500043India Department of Electrical Engineering Indian Institute of TechnologyDelhi 110016India Department of Electronics and communication Engineering Indian Institute of Information TechnologyDesign and ManufacturingKanchipuram 600127India

Medium-duty/heavy-duty trucks(MD/HDTs)are yet to be included in India’s electric mobility *** the improvement of electric vehicle(EV)technologies,there is a growing interest in battery-electric trucks(BETs)from original equipment manufacturers(OEMs).The time is opportune to consider electrification as a future direction for road freight in ***,this article presents the results of an energy consumption simulation study of a BET under Indian *** study specifically considered an MDBET over a domestic drive *** energy consumption figures can facilitate future studies that analyze the technical and practical feasibility of BETs in the *** addition,the article provides the requisite groundwork for BET modeling for a simulation study by reviewing available EV powertrain systems and *** powertrain considerations are thereby obtained for a typical medium-duty/heavy-duty battery-electric truck(MD/HDBET)in the Indian context.

关键词： Electric truck heavy-duty battery electric truck medium-duty battery electric truck energy consumption vehicle powertrain

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SVD-MPE: An SVD-Based Vector Extrapolation Method of Polynomial Type

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Applied Mathematics 2016年第11期7卷 1260-1278页

作者： avram Sidi computer Science Department Technion-Israel Institute of Technology Haifa Israel

An important problem that arises in different areas of science and engineering is that of computing the limits of sequences of vectors , where , N being very large. Such sequences arise, for example, in the solution of systems of linear or nonlinear equations by fixed-point iterative methods, and are simply the required solutions. In most cases of interest, however, these sequences converge to their limits extremely slowly. One practical way to make the sequences converge more quickly is to apply to them vector extrapolation methods. Two types of methods exist in the literature: polynomial type methods and epsilon algorithms. In most applications, the polynomial type methods have proved to be superior convergence accelerators. Three polynomial type methods are known, and these are the minimal polynomial extrapolation (MPE), the reduced rank extrapolation (RRE), and the modified minimal polynomial extrapolation (MMPE). In this work, we develop yet another polynomial type method, which is based on the singular value decomposition, as well as the ideas that lead to MPE. We denote this new method by SVD-MPE. We also design a numerically stable algorithm for its implementation, whose computational cost and storage requirements are minimal. Finally, we illustrate the use of SVD-MPE with numerical examples.

关键词： Vector Extrapolation Minimal Polynomial Extrapolation Singular Value Decomposition Krylov Subspace Methods

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Neuroimaging brain growth charts:A road to mental health

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Psychoradiology 2021年第4期1卷 272-286页

作者： Li-Zhen chen avram JHolmes Xi-Nian Zuo Qi Dong State Key Laboratory of cognitive Neuroscience and Learning Beijing Normal UniversityBeijing 100875China Department of Psychology Yale UniversityNew HavenCT 06511USA Department of Psychiatry Yale UniversityNew HavenCT 06511USA National Basic Science Data center Beijing 100190China Developmental Population Neuroscience Research center International Data Group/McGovern Institute for Brain ResearchBeijing Normal UniversityBeijing 100875China Research center for Lifespan Development of Mind and Brain Institute of PsychologyChinese Academy of SciencesBeijing 100101China

Mental disorders are common health concerns and contribute to a heavy global burden on our modern *** is challenging to identify and treat them *** evidence suggests the incidence of various psychiatric and behavioral disorders is closely related to the atypical development of brain structure and *** identification and understanding of atypical brain development provide chances for clinicians to detect mental disorders earlier,perhaps even prior to onset,and treat them more *** invaluable and necessary method in identifying and monitoring atypical brain development are growth charts of typically developing individuals in the *** brain growth charts can offer a series of standard references on typical neurodevelopment,representing an important resource for the scientific and medical *** the present paper,we review the relationship between mental disorders and atypical brain development from a perspective of normative brain development by surveying the recent progress in the development of brain growth charts,including four aspects on growth chart utility:1)cohorts,2)measures,3)mechanisms,and 4)clinical *** doing so,we seek to clarify the challenges and opportunities in charting brain growth,and to promote the application of brain growth charts in clinical practice.

关键词： growth chart development neuroimaging reliability mental health

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Prognostic significance of tumor immune microenvironment and immunotherapy:Novel insights and future perspectives in gastric cancer

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World Journal of Gastroenterology 2018年第32期24卷 3583-3616页

作者： Daniela cornelia Lazǎr Mihaela Flavia avram Ioan Romosan Mǎrioara cornianu Sorina Tǎan Adrian Goldis Department of Internal Medicine I University Medical ClinicUniversity of Medicine and Pharmacy"Victor Babes"Timisoara 300041Timis CountyRomania Department of Surgery X 1st Surgery ClinicUniversity of Medicine and Pharmacy"Victor Babes"Timisoara 300041Timis CountyRomania Department of Pathology University of Medicine and Pharmacy"Victor Babes"Timisoara 300041Timis CountyRomania Department of Gastroenterology and Hepatology University of Medicine and Pharmacy"Victor Babes"Timisoara 300041Timis CountyRomania

Despite a decrease in gastric cancer incidence, the development of novel biologic agents and combined therapeutic strategies, the prognosis of gastric cancer remains poor. Recently, the introduction of modern immunotherapy, especially using immune checkpoint inhibitors, led to an improved prognosis in many cancers. The use of immunotherapy was also associated with manageable adverse event profiles and promising results in the treatment of patients with gastric cancer, especially in heavily pretreated patients. These data have led to an accelerated approval of some checkpoint inhibitors in this setting. Understanding the complex relationship between the host immune microenvironment and tumor and the immune escape phenomenon leading to cancer occurrence and progression will subsequently lead to the identification of prognostic immune markers. Furthermore, this understanding will result in the discovery of both new mechanisms for blocking tumor immunosuppressive signals and pathways to stimulate the local immune response by targeting and modulating different subsets of immune cells. Due to the molecular heterogeneity of gastric cancers associated with differentclinico-biologic parameters, immune markers expression and prognosis, novel immunotherapy algorithms should be personalized and addressed to selected subsets of gastric tumors, which have been proven to elicit the best clinical responses. Future perspectives in the treatment of gastric cancer include tailored dual immunotherapies or a combination of immunotherapy with other targeted agents with synergistic antitumor effects.

关键词： immunotherapy prognostic significance tumor immune microenvironment immune checkpoint inhibitors gastric cancer

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Primary Small Bowel Melanoma or Small Bowel Metastasis with Vanishing Primary cutaneous Lesion

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case Reports in clinical Medicine 2022年第3期11卷 63-71页

作者： Dana criṣan Andreea Ardelean Mihaela coman Laurenţiu Stoicescu Ioana Rusu Nadim Al Hajjar Tudor Pop Sorin criṣ an constantin Bodolea Lucreţ ia avram Faculty of Medicine Iuliu Hatieganu University of Medicine and Pharmacy Cluj-Napoca Romania clinical Municipal Hospital Cluj-Napoca Romania 3rd Medical clinic “Octavian Fodor” Regional Institute of Gastroenterology and Hepatology cluj Cluj-Napoca Romania

The small bowel represents one of the main sites for cutaneous melanoma metastasis;however, numerous cases of primary intestinal melanoma have recently been described. In view of this, we present the case of a 39-year-old woman admitted for nausea, heartburn, abdominal pain, change in bowel habits and weight loss. contrast-enhanced cT revealed a small bowel mass. Surgical resection of a 6 cm ileal tumour with regional mesenteric lymphadenectomy and end-to-end anastomosis was performed. Histopathological findings indicated the presence of an ileal melanoma metastasis. Subsequent dermatological examination identified a cutaneous lesion on the right forearm, however no malignant cells were found at the histopathological exam. Whole body PET cT with FDG identified multiple frontal and parietal lesions. Genetic testing was positive for BRAF gene V600 E mutation. The patient underwent multiple neurosurgical procedures for the resection of cerebral metastases. Palliative external radiation and chemotherapy was also attempted. After approximately 2 years after the diagnosis, the patient died following multiple episodes of intracranial hypertension.

关键词： Melanoma Small Bowel cerebral Metastasis

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Information on a New Field of Knowledge： Metallurgical Econology

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Journal of Environmental Science and Engineering(B) 2012年第2期1卷 137-143页

作者： avram Nicolae cristian Predescu Maria Nicolae Ecaterina Matei Mirela Sohaciu Science Material and Engineering Faculty Politehnica University of Bucharest Bucharest 040062 Romania

A new branch of science called econology is being defined and shortly characterized as studying the economics-ecology-energy associations (3E or E3 associations). In the future, this must be transformed into tehnology (T)-economy-energy-ecology, so that the symbol of the econology shall be TE3. Being a new field, it becomes necessary to define and characterize the specific methodological tools. That"s why the paper examines the following indices: (1) specific consumption of primary carbon; (2) specific consumption of primary negentropy; (3) reintegration rate of secondary materials and energy. Also, the following issues are presented: (1) the indirect pollution mechanism in metallurgy; (2) analysis of pollution issues by principle "think globally, act locally".

关键词：知识领域冶金生态能源信息辅助材料污染机制污染问题经济学

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计算机辅助系统在上消化道内镜质量监测和胃病变评估中的作用

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Gastroenterology Report 2021年第3期9卷 185-204,I0001页

作者： Daniela cornelia Lazar Mihaela Flavia avram Alexandra corina Faur Ioan Romosan Adrian Goldis Department V of Internal Medicine I Discipline of Internal Medicine IV“Victor Babes”University of Medicine and Pharmacy TimisoaraRomaniaTimisoaraRomania Department of Surgery X 1st Surgery Discipline“Victor Babes”University of Medicine and Pharmacy TimisoaraRomaniaTimisoaraRomania Department I Discipline of Anatomy and Embriology“Victor Babes”University of Medicine and Pharmacy TimisoaraRomaniaTimisoaraRomania Department VII of Internal Medicine II Discipline of Gastroenterology and Hepatology“Victor Babes”University of Medicine and Pharmacy TimisoaraRomaniaTimisoaraRomania

本文通过文献综述,对计算机辅助系统在食管胃十二指肠镜质量监测和胃病变评估方面的应用价值进行了分析。目前数据表明,计算机辅助系统能为上消化道内镜检查提供良好的质量控制,并能较为准确地检出胃恶性肿瘤及癌前病变,与经验丰富的内... 详细信息

本文通过文献综述,对计算机辅助系统在食管胃十二指肠镜质量监测和胃病变评估方面的应用价值进行了分析。目前数据表明,计算机辅助系统能为上消化道内镜检查提供良好的质量控制,并能较为准确地检出胃恶性肿瘤及癌前病变,与经验丰富的内镜医师相当,甚至更佳。同时,人工智能(AI)能够为胃癌患者确定最佳治疗策略,即根据肿瘤浸润深度进行内镜或手术切除,从而在保证生活质量和远期预后的同时,避免不必要的手术干预。各种不同算法的AI应用于上消化道内镜检查中,无论是普通的白光内镜,还是一些专业内镜中心所采用的新型内镜技术,都显示出良好的效果。目前在研的一些关于AI及计算机辅助诊断系统嵌入内镜设备的临床试验,其结果值得期待,有望实现AI内镜系统在未来的真实应用,突破当前计算机辅助系统的不足,提高检测效能。这些改进能为胃癌患者提供更好的诊疗策略。而且,将AI算法融入到内镜设备,加之包含内镜图像的大数据,或可进一步拓展上消化道内镜的应用空间,包括远程医疗和疑难病例的会诊。

关键词：上消化道内镜计算机辅助系统胃恶性肿瘤疑难病例胃癌患者内镜中心诊疗策略质量监测

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电子设备的热控制与分析

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1992年

作者：（美）克劳斯（Kraus Allan D.）（美）巴科恩（bar-c.hen avram）赵抈殳等译

书名原文:Thermal analysis and control of electronic equipment:阐述了国外目前采用的先进热控制技术及其发展状况。其中包括:传热学流体力学的基本概念、电子元器件及新型的冷却技术等。

ISBN: (纸本)7118008583

关键词：电子设备热控制

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