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Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush vij H.C.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Drivers for Inter-city Innovation Networks Across Chinese Cities:Modelling Physical Versus Intangible Effects

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Chinese geographical Science 2024年第4期34卷 706-721页

作者： gAO Yujie SCHerNgELL Thomas NEULÄNDTNer martina School of Applied Economics Renmin University of ChinaBeijing 100872China Center for Innovation Systems&Policy Austrian Institute of TechnologyVienna 1210Austria

Cross-region innovation is widely recognized as an important source of the long-term regional innovation *** the recent past,a growing number of studies has investigated the network structure and mechanisms of cross-region innovation collaboration in various ***,existing research mainly focuses on physical effects,such as geographical distance and high-speed railway *** studies ignore the intangible drivers in a changing environment,the more digitalized economy and the increasingly solidified innovation network ***,the focus of this study is on estimating determinants of innovation networks,especially on intangible drivers,which have been largely neglected so *** city-level data of Chinese patents(excluding Hong Kong,Macao,and Taiwan Province of China),we trace innovation networks across Chinese cities over a long period of *** integrating a measure on Information and Communications Technology(ICT)development gap and network structural effects into the general proximity framework,this paper explores the changing mechanisms of Chinese innovation networks from a new *** results show that the structure of cross-region innovation networks has changed in *** mechanisms behind this development,the results confirm the increasingly important role of intangible drivers in Chinese inter-city innovation collaboration when controlling for effects of physical proximity,such as geographical *** digitalization and coordinated development are the mainstream trends in China and other developing countries,these countries'inter-city innovation collaboration patterns will witness dramatic changes under the influence of intangible drivers.

关键词： inter-city innovation network co-patents information and communications technology development network structural effect spatial interaction model China

An analytical model to estimate the time delay to reach spontaneous ignition considering heat loss in oil reservoirs

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Petroleum Science 2024年第4期21卷 2469-2474页

作者： James J.Sheng er-Long Yang College of Petroleum Engineering Northeast Petroleum University

During air injection into an oil reservoir, an oxidation reaction generates some heat to raise the reservoir temperature. When the reservoir temperature reaches an ignition temperature, spontaneous ignition occurs. There is a time delay from the injection to ignition. There are mixed results regarding the feasibility of spontaneous ignition in real-field projects and in laboratory experiments. No analytical model is available in the literature to estimate the oxidation time required to reach spontaneous ignition with heat *** paper discusses the feasibility of spontaneous ignition from theoretical points and experimental and field project observations. An analytical model considering heat loss is proposed. Analytical models with and without heat loss investigate the factors that affect spontaneous ignition. Based on the discussion and investigations, we find that it is more difficult for spontaneous ignition to occur in laboratory experiments than in oil reservoirs; spontaneous ignition is strongly affected by the initial reservoir temperature, oil activity, and heat loss; spontaneous ignition is only possible when the initial reservoir temperature is high, the oil oxidation rate is high, and the heat loss is low.

关键词： Spontaneous ignition Time delay Air injection Heat loss Low temperature oxidation Combustion

Combined hepatocellular cholangiocarcinoma: A clinicopathological update

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World Journal of Hepatology 2024年第5期16卷 766-775页

作者： Mukul vij Fadl H Veerankutty Ashwin Rammohan Mohamed Rela Department of Pathology Institute of Liver Disease and TransplantationChennai 600044India Comprehensive Liver Care Institute VPS LakeshoreCochin 682040India Institute of Liver Disease and Transplantation Dr.Rela Institute and Medical CentreChennai 600044India

Combined hepatocellular-cholangiocarcinoma(cHCC-CCA)is a rare primary liver cancer associated with an appalling *** diagnosis and manage-ment of this entity have been challenging to physicians,radiologists,surgeons,pathologists,and oncologists *** diagnostic and prognostic value of biomarkers such as the immunohistochemical expression of nestin,a progenitor cell marker,have been explored *** a better understanding of biology and the clinical course of cHCC-CCA,newer treatment modalities like immune checkpoint inhibitors are being tried to improve the survival of patients with this rare *** this review,we give an account of the recent developments in the pathology,diagnostic approach,and management of cHCC-CCA.

关键词： Combined hepatocellular-cholangiocarcinoma Immunotherapy Nestin Hepatocellular carcinoma Cholangiocarcinoma Liver cancer Biomarker Immune checkpoint inhibitors Pathology genomic landscape

Comparison of engineering failures and seismic responses of 500 kV transformer-bushing systems in the 2022 Luding earthquake

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 1029-1041页

作者： Zhu Wang Wu Ming’er Xie Qiang Department of Structural Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures(Tongji University) Shanghai 200092China

Cemented and mechanically clamped types of end fittings(fitting-C and fitting-M)are commonly used in transformer *** the Luding Ms 6.8 earthquake that occurred in China on September 5,2022,all transformer bushings with the two types of end fittings in a 500 kV substation were ***-earthquake field investigations were conducted,and the failures of the two types of bushings were *** elementary simulation models of the transformer-bushing systems were developed to simulate the engineering failures,and further compute their seismic responses for *** results indicate that the hitch lugs of the connection flange are structurally harmful to seismic ***-M can decrease the bending stiffness of the bushing due to the flexible sealing rubber *** it provides a more flexible connection that dissipates energy,the peak accelerations and relative displacements at the top of the bushing are significantly lower than those of the bushing with *** with fitting-C,fitting-M transfers the high-stress areas from the connection flange to the root of the porcelain,so the latter becomes the most vulnerable ***-M increases the failure risk of the low-strength porcelain,indicating the unsuitability of applying it in high-intensity fortification regions.

关键词： transformer bushing end fitting Luding earthquake,engineering failure seismic responses

Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

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Water Science and Engineering 2024年第2期17卷 177-186页

作者： er-feng Zhao Xin Li Chong-shi gu The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China NationalEngineering Research Centerof Water Resources Eficient Utilization and Engineering Safety Hohai UniversityNanjing 20098China

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in *** control is essential to long-term operation of these *** study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in ***,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect *** findings revealed the governing mechanism of main ***,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch *** model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation ***,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam ***,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably *** of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan *** findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

关键词： Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model

Nanomedicine targeting ferroptosis to overcome anticancer therapeutic resistance

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Science China(Life Sciences) 2024年第1期67卷 19-40页

作者： Jing Cai Xiaoding Xu Phei er Saw guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and gene Regulation Guangdong-Hong Kong Joint Laboratory for RNA MedicineMedical Research CenterSun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China Nanhai Translational Innovation Center of Precision Immunology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityFoshan 528200China

A potential reason for the failure of tumor therapies is treatment *** to chemotherapy,radiotherapy,and immunotherapy continues to be a major obstacle in clinic,resulting in tumor recurrence and *** major mechanisms of therapy resistance are inhibitions of cell deaths,like apoptosis and necrosis,through drug inactivation and excretion,repair of DNA damage,tumor heterogeneity,or changes in tumor microenvironment,*** studies have shown that ferroptosis play a major role in therapies resistance by inducing phospholipid peroxidation and iron-dependent cell *** ferroptosis inducers in combination with clinical treatment techniques have been used to enhance the effect in tumor ***,versatile ferroptosis nanoinducers exhibit an extensive range of functions in reversing therapy resistance,including directly triggering ferroptosis and feedback ***,we provide a detailed description of the design,mechanism,and therapeutic application of ferroptosis-mediated synergistic tumor *** also discuss the prospect and challenge of nanomedicine in tumor therapy resistance by regulating ferroptosis and combination therapy.

关键词： ferroptosis cancer therapy therapy resistance nanoinducers

Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae

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Research in Astronomy and Astrophysics 2024年第4期24卷 183-191页

作者： Zhenyu Wang Jujia Zhang Xinzhong er Jinming Bai Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients *** telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to *** considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by *** best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 *** this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia.

关键词： (stars:)supernovae:general (cosmology:)cosmological parameters telescopes

Social networks of reintroduced Przewalski's horses in the great gobi B Strictly Protected Area (Mongolia)

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Current Zoology 2024年第2期70卷 182-194页

作者： Anna Bernatkova ganbaatar Oyunsaikhan Jaroslav Simek martina Komarkova Francisco Ceacero Faculty of Tropical AgriSciences Czech University of Life Sciences PragueCzech Republic great gobi B Strictly Protected Area Takhin TalMongolia Zoo Praha U Trojského zamku 120/3PragueCzech Republic

Analyzing social networks is a powerful tool for understanding the ecology of social *** most studies focus on the role of each group member,few compare groups with different *** current population of Przewalski's horses Equus ferus przewalskii at the great gobi B Strictly Protected Area(Mongolia)includes groups of wild-born and captive-bred individuals with different experiences with the area(acclimatizing,long-term reintroduced,and wild-born),therefore serving as an ideal natural behavioral *** filmed 11 groups for 141.5 hours in summer 2018(July),late spring 2019(May,June),and autumn 2019(September,October).Affiliative and agonistic interactions were recorded,and social networks were *** tested the influence of origin,experience,season,sex,age,relative time belonging to the group,relat-edness,and dominance rank on different network indices at the individual and group *** found that groups with greater experience in the area are generally better connected than members of the newly formed ***,these strong networks were created by wild-born individuals with very low interaction *** the contrary,inexperienced groups composed of captive-bred individuals displayed many inter actions but created weak social *** results show a trend of behavioral transition from acclimatizing through long-term reintroduced to wild-born groups,supporting that the newly formed groups of released Przewalski's horses need time to display the typical social behavior patterns of wild-born ***-term monitoring of released Przewalski's horses is recommended to promote the success of this reintroduction program.

关键词： Przewalski's horses reintroduction social behavior soft-release.