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Volcanically Driven Terrestrial Environmental Perturbations during the Carnian Pluvial Episode in the Eastern Tethys

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 753-770页

作者： naveed ur rahman XIAN Benzhong FANG Linhao CHEN Sirui CHEN Peng Zaheen ULLAH WANG Pengyu National Key Laboratory of Petroleum Resources and Engineering Beijing 102249China College of Geosciences China University of PetroleumBeijing 102249China Centre for Earth and Space Sciences University of SwatSwat 19120Pakistan

The Carnian Pluvial Episode(CPE)fingerprints global environmental perturbations and biological extinction on land and oceans and is potentially linked to the Wrangellia Large Igneous Province(LIP).However,the correlation between terrestrial environmental changes and Wrangellia volcanism in the Ordos Basin during the CPE remains poorly *** of negative carbon isotopic excursions(NCIEs),mercury(Hg),Hg/TOC,and Hg enrichment factor(HgEF)from oil shales in a large-scale terrestrial Ordos Basin in the Eastern Tethys were correlated with marine and other terrestrial *** three significant NCIEs in the study section were consistently correlated with those in the CPE successions of Europe,the UK,and South and North *** U-Pb geochronology indicates a Ladinian-Carnian age for the Chang 7 Member.A comprehensive overview of the geochronology,NCIE correlation,and previous bio-and chronostratigraphic frameworks shows that the Ladinian-Carnian boundary is located in the lower part of Chang 7 in the Yishicun *** may be a more reliable proxy for tracing volcanic eruptions than the Hg/TOC ratio because the accumulation rates of TOC content largely vary in terrestrial and marine *** records of Hg,Hg/TOC,HgEF,and NCIEs in the Ordos Basin aligned with Carnian successions worldwide and were marked by similar anomalies,indicating a global response to the Wrangellia LIP during the ***,a warm-humid climate,enhancement of detrital input,and NCIEs are synchronous with the CPE interval in the Ordos Basin,which suggests that the CPE combined with the regional Qinling Orogeny should dominate the enhanced rate of terrigenous input and paleoenvironmental evolution in the Ordos Basin.

关键词： Chang 7 Member oil shale Carnian Pluvial Episode volcanism environmental perturbations

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Regulation of the order-disorder phase transition in a Cs_(2)NaFeCl_(6) double perovskite towards reversible thermochromic application

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Journal of Semiconductors 2021年第7期42卷 44-57页

作者： Wenzhe Li naveed ur rahman Yeming Xian Hang Yin Yunkai Bao Yi Long Songyang Yuan Yangyi Zhang Yaxuan Yuan Jiandong Fan Institute of New Energy Technology Department of Electronic Science and EngineeringCollege of Information Science and TechnologyJinan UniversityGuangzhou 510632China

Multifunctional lead-free double perovskites demonstrate remarkable potential towards applications in various ***,an environmentally-friendly,low-cost,high-throughput Cs_(2)NaFeCl_(6) single crystal with exceedingly high thermal stability is designed and *** obtains a cubic lattice system in the temperature range of 80-500 K,accompanied by a completely reversible chromatic variation ranging from yellow to ***,the intriguing thermochromism is proved to own extremely high reproducibility(over 1000 cycles)without a hysteretic effect,originating from its structural flexibility that including(i)the noteworthy distortion/deformation of[NaCl_(6)]5−and[FeCl_(6)]3−octahedra;(ii)order-disorder arrangement transition of[NaCl_(6)]5−and[FeCl6]3−octahedra as the function of *** study paves the way towards a new class of smart windows and camouflage coatings with an unprecedented colour range based on a Cs_(2)NaFeCl_(6) perovskite.

关键词： lead-free perovskite Cs_(2)NaFeCl_(6)single crystal thermochromism crystallographic structure order-disorder phase transition

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Enhanced novel reddish orange emission in Sr1-xCaSiO4:xSm3+ by codoping of K+

Enhanced novel reddish orange emission in Sr1-xCaSiO4:xSm3+ ...

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中国稀土学会2017学术年会

作者： Wasim Ullah Khan Junhao Li Jing Yan Xiaohui Li Lei Zhou naveed ur rahman Dilfaraz Khan Jianxin Shi Mingmei Wu Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen University School of Marine Science Sun Yat-Sen University

Novel phosphors of Sr CaSiO:xSm and SrCaSiO:0.015Sm,x K were synthesized via high-temperature solid state *** phases and luminescent properties were *** the excitation of 401 nm light,SrCaSiO:xSm emitted the characteristic reddish orange light peaked at 564,601 and 647 nm,and the intensity can be further enhanced for some extend by codoping of K+ ions as charge *** results of temperature dependent PL intensity show that the synthesized phosphors have a satisfactory thermal stability which suggest that SrCaSiO:0.02Sm,0.015 K is a promising reddish orange emitting phosphor for application in UV-based WLEDs.

关键词： Synthesized Luminescence Properties Orange–red emitting WLEDs

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Th-Shaped Tunable Multi-Band Antenna for Modern Wireless Applications

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Computers, Materials & Continua 2023年第2期74卷 2517-2530页

作者： Wasi ur Rehman Khan Muhammad Fawad Khan Muhammad Irfan Sadiq Ullah naveed Mufti Usman Ali Rizwan Ullah Fazal Muhammad Saifur rahman Faisal Althobiani Mohammed Alshareef Mohammad E.Gommosani Department of Telecommunication Engineering University of Engineering and TechnologyMardanPakistan Electrical Engineering Department College of EngineeringNajran UniversityNajranSaudi Arabia Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Natural Science Department Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia

A compact,reconfigurable antenna supporting multiple wireless services with a minimum number of switches is found lacking in literature and the same became the focus and outcome of this *** was achieved by designing a Th-Shaped frequency reconfigurable multi-band microstrip planar antenna,based on use of a single switch within the radiating structure of the *** frequency bands(i.e.,2007–2501 MHz,3660–3983MHz and 9341–1046 MHz)can be operated with the switch in the ON switch *** the OFF state of the switch,the antenna operates within the 2577–3280MHz and 9379–1033MHz *** proposed antenna shows an acceptable input impedance match with Voltage Standing Wave Ratio(VSWR)less than *** peak radiation efficiency of the antenna is 82%.A reasonable gain is obtained from 1.22 to 3.31 dB within the operating bands is *** proposed antenna supports UniversalMobile Telecommunication System(UMTS)-1920 to 2170 MHz,Worldwide Interoperability and Microwave Access(WiMAX)/Wireless Broadband/(Long Term Evolution)LTE2500–2500 to 2690 MHz,Fifth Generation(5G)-2500/3500 MHz,Wireless Fidelity(Wi-Fi)/Bluetooth-2400 to 2480 MHz,and Satellite communication applications in X-Band-8000 to 12000 *** overall planar dimension of the proposed antenna is 40×*** antennawas designed,along with the parametric study,using Electromagnetic(EM)simulation *** antenna prototype is fabricated for experimental validation with the simulated *** proposed antenna is low profile,tunable,lightweight,cheap to fabricate and highly efficient and hence is deemed suitable for use in modern wireless communication electronic devices.

关键词： Antenna design reconfigurable antenna satellite communication frequency bands

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Study on the synthesis of spin labeled poly(styrene-co-maleic acid)s and their segmental motion

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Magnetic Resonance Letters 2022年第2期2卷 80-90,I0002页

作者： Kaleem-ur-rahman naveed Li Wang Haojie Yu Qian Zhang Wei Xiong Raja Summe Ullah Ahsan Nazir Muhammad Usman Shah Fahad Amin Khan Md Alim Uddin Di Shen State Key Laboratory of Chemical Engineering College of Chemical&Biological EngineeringZhejiang UniversityHangzhou310027China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

Study of the segmental mobility of polymer chains is important when the polymer is used as drag reduction agents of crude *** spin resonance(ESR)spectroscopy can provide important information about segmental dynamics of polymer chains,which is related to their *** this article,we employed an amphiphilic polymer to study the effect of hydrophilic/hydrophobic balance of the polymers on the segmental motion of polymer ***(styrene-co-maleic acid)(PSMA)was spin labeled with 4-amino TEMPO radicals by increasing the concentration of radical moiety on the polymer *** PSMA and spin labeled-PSMAs(SL-PSMAs)were characterized by nuclear magnetic resonance(NMR),Fourier transform infrared(FT-IR)spectroscopy,Cyclic voltammetry(CV)and ESR ***-polymer complexes(IPCs)of SL-PSMA-2 were prepared by employing polyethylene glycols(PEGs)of varying molecular *** results showed that the increased hydrophobic interactions of nitroxide radicals on the SLPSMAs’chains reduced the rotational mobility of spin labels and the random coil-toglobular transition of polymer chains occurred at higher pH value for SL-PSMAs,which showed a slow motion component in the ESR spectra of ***,by increasing the molecular weight of PEGs in IPCs the complexation was increased,which also reduced the rotational motion of spin labels due to interpolymer hydrogen bonding causing a slow motion component in the ESR spectra.©2021 The Authors.

关键词： Electron spin resonance(ESR) Spin labeling Nitroxide radicals poly(styrene-co-maleic acid)s Segmental motion

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Location-allocation modeling for emergency evacuation planning with GIS and remote sensing:A case study of Northeast Bangladesh

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Geoscience Frontiers 2021年第3期12卷 169-185页

作者： Mahfuzur rahman Ningsheng Chen MdMonirul Islam Ashraf Dewan Hamid Reza Pourghasemi Rana Muhammad AliWashakh Nirdesh Nepal Shufeng Tian Hamid Faiz Mehtab Alam naveed Ahmed Key Laboratory for Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment(IMHE)Chinese Academy of Sciences(CAS)Chengdu 610041China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Department of Civil Engineering International University of Business Agriculture and Technology(IUBAT)Dhaka 1230Bangladesh School of Earth and Planetary Sciences Curtin UniversityKent StBentleyWA 6102Australia Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran School of Architecture Neijiang Normal UniversityNeijiang 641100China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Global Institute for Interdisciplinary Studies Kathmandu 3084Nepal

This work developed models to identify optimal spatial distribution of emergency evacuation centers(EECs)such as schools,colleges,hospitals,and fire stations to improve flood emergency planning in the Sylhet region of northeastern *** use of location-allocation models(LAMs)for evacuation in regard to flood victims is essential to minimize disaster *** the first step,flood susceptibility maps were developed using machine learning models(MLMs),including:Levenberg-Marquardt back propagation(LM-BP)neural network and decision trees(DT)and multi-criteria decision making(MCDM)*** of the MLMs and MCDM techniques were assessed considering the area under the receiver operating characteristic(AurOC)*** approaches in a geographic information system(GIS)for four well-known LAM problems affecting emergency rescue time are proposed:maximal covering location problem(MCLP),the maximize attendance(MA),p-median problem(PMP),and the location set covering problem(LSCP).The results showed that existing EECs were not optimally distributed,and that some areas were not adequately served by EECs(i.e.,not all demand points could be reached within a 60-min travel time).We concluded that the proposed models can be used to improve planning of the distribution of EECs,and that application of the models could contribute to reducing human casualties,property losses,and improve emergency operation.

关键词： Natural disasters Emergency evacuation centers Flooding Machine learning Multi-criteria decision making Location-allocation model

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自旋标记聚（N-异丙基丙烯酰胺-co-丙基丙烯酸）的合成及其电子自旋共振的研究

自旋标记聚（N-异丙基丙烯酰胺-co-丙基丙烯酸）的合成及其电子自...

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2018第二十届全国波谱学学术年会

作者： Kaleem-ur-rahman naveed 王立俞豪杰刘纪扬浙江大学化学工程联合国家重点实验室浙江大学

＜正＞对于聚合物来说,了解它们的分子动力学进而调整它们的宏观性质是很重要的。电子自旋共振谱现在已经成为认识聚合物体系内部动力学的一种技术,而其他现代分析技术则无法实现这一目的。许多聚合物性质如减阻效率等可通过自旋标记和...

＜正＞对于聚合物来说,了解它们的分子动力学进而调整它们的宏观性质是很重要的。电子自旋共振谱现在已经成为认识聚合物体系内部动力学的一种技术,而其他现代分析技术则无法实现这一目的。许多聚合物性质如减阻效率等可通过自旋标记和探针分析而与聚合物链的链段动力学直接相关联。在本研究中,合成了聚（N-异丙基丙烯酰胺-co-丙基丙烯酸）,随后

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