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Exploring the occurrence rate of PMSE-Es by Digisonde at Tromsø

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Earth and Planetary Physics 2021年第2期5卷 187-195页

作者： HaiLong Li ShuCan Ge Lin Meng MaoYan Wang abdur rauf Safi Ullah School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

Polar mesosphere summer echoes(PMSE)are observed simultaneously with Digisonde and EISCAT VHF *** phenomenon of irregular Es layers is called PMSE-like or PMSE-Es(Polar Mesosphere Summer Echoes-Es)and has some relationship with real *** this paper,the characteristics of irregular Es layers at 80–100 km were observed by Digisonde at Tromsøduring 2003–2014 are statistically analyzed with *** diurnal,day-to-day and year-to-year variations and discrepancies of occurrence rate between PMSE and PMSE-Es are compared with the statistical results observed by Esrange MST radar(ESRAD),and the reasons are *** results show that the trends in the occurrence rate of PMSE-Es are similar to the trends in the occurrence rate of PMSE,but there are some notable *** occurrence rate of PMSE-Es is much lower than the occurrence rate of *** minimum value of PMSE-Es appears 1–2 hours earlier than the minimum value of the PMSE occurrence rate,while PMSE-Es appear earlier than PMSE in the *** addition,there is a significant positive correlation between the annual average occurrence rates of PMSE and *** is a relatively important occurrence in the polar *** of its characteristics can provide new ideas and methods for studying the formation mechanism of PMSE.

关键词： Polar mesosphere summer echoes Digisonde EISCAT VHF radar PMSE-Es Esrange MST radar

Effect of ions on conductivity and permittivity in the Polar Mesosphere Summer Echoes region

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Earth and Planetary Physics 2021年第2期5卷 196-204页

作者： Safi Ullah HaiLong Li abdur rauf Lin Meng Bin Wang ShuCan Ge MaoYan Wang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Terahertz Science and Technology Key Laboratory of Sichuan Province Chengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

For the first time,the effect of ions on complex conductivity and permittivity of dusty plasma at Polar Mesosphere Summer Echoes(PMSE)altitude is *** of ions higher mass and smaller thermal velocity,generally,their effects are not considered in the study of electromagnetic properties of dusty *** this study,we modified the equations of conductivity and permittivity by adding the effect of *** the PMSE altitude region between 80 and 90 km,a local reduction in electron density(i.e.,an electron biteout),is produced by electron absorption onto dust *** bite-out condition contains high dust density and smaller electron *** simulation results in comparatively strong bite-out conditions,we found that the ion effects on conductivity become significant with smaller dust size,lower electron temperature,and lower neutral *** comparatively weak bite-out conditions,the ion effects on conductivity become significant with larger dust size,higher electron temperature,and higher neutral *** the other hand,for different dust sizes,electron temperatures and neutral density,the ion effects on complex permittivity become significant only in very strong bite-out *** on these simulation results,we conclude that,in the absence of electron bite-out conditions,the effect of ions on complex conductivity and permittivity is not significant and can be ***,during bite-out conditions,the effect of ions becomes significant and cannot be ignored because it significantly changes the conductivity and permittivity of dusty plasmas.

关键词： PMSE electromagnetic waves collision and charging effect conductivity and permittivity

Numerical Analysis of Artificial Electron Heating Effects on Polar Mesospheric Winter Echoes

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Journal of Electronic Science and Technology 2020年第3期18卷 287-295页

作者： Safi Ullah Hai-Long Li abdur rauf Lu-Yao Fu Mao-Yan Wang Lin Meng School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

In this paper,an analytical model is used to analyze the modulated polar mesospheric winter echoes(PMWE).The winter parameters were introduced to simulate the effects of different parameters during the artificial electron heating of *** important role of the charged dust particle in the creation of PMWE is confirmed *** is found that during the heating of PMWE,the increases of the dust size,dust charge,electron temperature,initial electron density,and ion-neutral collision frequency cause the increase of the electron density irregularity,and hence the PMWE ***,with increasing the dust density,the electron density irregularity and the PMWE strength decrease.

关键词： Artificial ionospheric heating electron density irregularities polar mesospheric winter echoes(PMWE) space plasma physics(numerical simulation)

Investigation of PMSE echoes characteristics using the discontinuous EISCAT UHF observation and its relation with space environment

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Advances in Polar Science 2019年第2期30卷 132-138页

作者： abdur rauf LI Hailong Safi ULLAH WANG Maoyan MENG Lin School of Electronic Science and Engineering University of Electronic Science and Technology of China Chengdu 610054 China School of Physics University of Electronic Science and Technology of China Chengdu 610054 China

The observations of Polar Mesosphere Summer Echoes (PMSE) were carried out using the sporadic data of EISCAT UHF radar during the summer season from 2004 to 2015. There were 25 h of PMSE echoes with EISCAT UHF radar. PMSE echoes were mostly observed only during the early morning and fore-noon time. Moreover, the PMSE echoes are positively correlated with Lymanα radiation, but the correlation is non-significant. The occurrence of PMSE echoes in the early morning and fore-noon time and there positive correlation with Lymanαradiation suggests that solar radiations might be one important factor for PMSE echoes in this study. Very weak positive, but statistically non-significant correlation is found between PMSE occurrence rate and the local geomagneticK-indices. It is found that there is a matching between the variation in the occurrence rate of PMSE and noctilucent clouds (NLC) up to some extent and they are positively correlated. This positive correlation might support the earlier proposed idea about the role of ice particle size in producing PMSE echoes at higher frequencies.

关键词： PMSE echoes geomagnetic indices EISCAT UHF radar

On the radar frequency dependence of polar mesosphere summer echoes

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Earth and Planetary Physics 2020年第6期4卷 571-578页

作者： ShuCan Ge HaiLong Li Lin Meng MaoYan Wang Tong Xu Safi Ullah abdur rauf Abdel Hannachid School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China National Key Laboratory of Electromagnetic Environment China Research Institute of Radio Wave PropagationQingdao 266107China Department of Meteorology Stockholm UniversitySE-106-91StockholmSweden

Polar mesosphere summer echoes(PMSEs)are very strong radar echoes in the polar mesopause in local *** we present the frequency dependence of the volume reflectivity and the effect of energetic particle precipitation on modulated PMSEs by using PMSEs observations carried out by European Incoherent SCATter(EISCAT)heating equipment simultaneously with very high frequency(VHF)radar and ultra high frequency(UHF)radar on 12 July *** to the experimental observations,the PMSEs occurrence rate at VHF was much higher than that at UHF,and the altitude of the PMSEs maximum observed at VHF was higher than that at *** regions were observed by VHF radar between high energetic particle precipitation and the *** addition,highfrequency heating had a very limited impact on PMSEs when the UHF electron density was enhanced because of energetic particle *** addition,an updated qualitative method was used to study the relationship between volume reflectivity and *** volume reflectivity was found to be inversely proportional to the fourth power of radar *** theoretical and experimental results provide a definitive data foundation for further analysis and investigation of the physical mechanism of PMSEs.

关键词： Polar mesosphere summer echoes artificial electron heating volume reflectivity energetic particle precipitation

Influence of Ni/Mn ratio on magnetostructural transformation and magnetocaloric effect in Ni48-xCo2Mn38+xSn12(x=0,1.0,1.5,2.0,and 2.5)ferromagnetic shape memory alloys

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Chinese Physics B 2017年第9期26卷 428-432页

作者： Ishfaq Ahmad Shah Najam ul Hassan abdur rauf 刘俊龚元元徐桂舟徐锋 Jiangsu Key Laboratory of Advanced Micro&Nano Materials and Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Herbert Gleiter Institute of Nanoscience Nanjing University of Science and TechnologyNanjing 210094China

An investigation on the magnetostructural transformation and magnetocaloric properties of Ni48-xCo2Mn38＋xSn12（x = 0, 1.0, 1.5, 2.0, and 2.5） ferromagnetic shape memory alloys is carried out. With the partial replacement of Ni by Mn in the Ni_（48）Co2Mn38Sn12 alloy, the electron concentration decreases. As a result, the martensitic transformation temperature is decreased into the temperature window between the Curie-temperatures of austenite and martensite. Thus, the samples with x = 1.5 and 2.0 exhibit the magnetostructural transformation between the weak-magnetization martensite and ferromagnetic austenite at room temperature. The structural transformation can be induced not only by the temperature,but also by the magnetic field. Accompanied by the magnetic-field-induced magnetostructural transformation, a considerable magnetocaloric effect is observed. With the increase of x, the maximum entropy change decreases, but the effective magnetic cooling capacity increases.

关键词： Ni–Co–Mn–Sn alloy magnetostructural transformation magnetocaloric effect magnetic entropy change

Quantitative prediction of the bitterness of atomoxetine hydrochloride and taste-masked using hydroxypropyl-β-cyclodextrin:A biosensor evaluation and interaction study

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Asian Journal of Pharmaceutical Sciences 2020年第4期15卷 492-505页

作者： Shuying Li Ying Zhang abdur rauf Khan Shuwang He Yingxin Wang Jiangkang Xu Guangxi Zhai Department of Pharmaceutics College of PharmacyShandong UniversityJinan250012China Department of Pharmaceutical Development Shandong Dyne Marine Biopharmaceutical Limited CorporationRongcheng264300China

The bitterness of a drug is a major challenge for patient acceptability and compliance,especially for *** to the toxicity of medication,a human taste panel test has certain *** hydrochloride(HCl),which is used for the treatment of attention deficit/hyperactivity disorder(ADHD),has an extremely bitter *** aim of this work is to quantitatively predict the bitterness of atomoxetine HCl by a biosensor *** on the mechanism of detection of the electronic tongue(Etongue),the bitterness of atomoxetine HCl was evaluated,and it was found that its bitterness was similar to that of quinine *** bitterness threshold of atomoxetine HCl was 8.61μg/ml based on the Change of membrane Potential caused by Adsorption(CPA)value of the BT0 *** this study,the taste-masking efficiency of 2-hydroxypropyl-β-cyclodextrin(HP-β-CyD)was assessed by Euclidean distances on a principle component analysis(PCA)map with the SA402B Taste Sensing System,and the host–guest interactions were investigated by differential scanning calorimetry(DSC),powder X-ray diffraction(XRD),nuclear magnetic resonance(NMR)spectroscopy and scanning electron microscopy(SEM).Biosensor evaluation and characterization of the inclusion complex indicated that atomoxetine HCl could actively react with 2-hydroxypropyl-β-cyclodextrin.

关键词： Atomoxetine HCl E-tongue Quantitative prediction Host–guest interaction

Sedative and antinociceptive activities of two new sesquiterpenes isolated from Ricinus communis

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Chinese Journal of Natural Medicines 2018年第3期16卷 225-230页

作者： Umar Farooq Ajmal Khan Sadia Naz abdur rauf Haroon Khan Afsar Khan Irfan Ullah Syed Majid Bukhari Department of Chemistry COMSATS Institute of Information Technology UoN Chair of Oman's Medicinal Plants and Marine Natural Products University of Nizwa Department of Geology University of Swabi Anbar Department of Pharmacy Abdul Wali Khan University Department of Pharmacy Abasyn University

Two new sesquiterpenes, trivially named ricinusoids A(1) and ricinusoids B(2), were isolated from ethyl acetate fraction of Ricinus communis. The structures of new compounds were elucidated by detailed spectroscopic techniques, including 1 D-and 2 D-NMR, UV, IR spectroscopy, and mass spectrometry. The compounds(1-2) were also assessed for in-vivo sedative and analgesic like effects in open field and acetic acid induced writhing tests respectively at 5, 10, and 20 mg·kg^(–1) i.p. Pretreatment of both test compounds caused significant(P ≤ 0.05) reduction in locomotive activity like sedative agents and abdominal constrictions like analgesics. Both compounds(1-2) possessed marked sedative and antinociceptive effects in animal models.

关键词： Ricinus communis Sesquiterpenoids Euphorbiaceae Spectroscopic techniques Antinociceptive activity

In vivo sedative and muscle relaxants activity of Diospyros lotus L

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Asian Pacific Journal of Tropical Biomedicine 2015年第4期5卷 277-280页

作者： abdur rauf Ghias Uddin Bina Shaheen Siddiqui Haroon Khan Institute of Chemical Sciences University of Peshawar H.E.J. Research Institute of Chemistry International Center for Chemical and Biological Sciences University of Karachi Department of Pharmacy Abdul Wali Khan University

Objective: To evaluate the sedative effect of Diospyros lotus L(D. lotus) extract in mice using the open field and Rota rod ***: For the sedative and muscle relaxants activities of extract/fractions of the plant, invivo open field and phenobarbitone-induced sleeping time were used, while the Roda rod test was employed in animals for the assessment of muscle relaxant ***: Results from this investigation revealed that the extracts of D. lotus have exhibited significant sedative effect in mice(45.98%) at 100 mg/kg i.p. When the extract was partitioned with different solvents, the n-hexane fraction was inactive whereas the chloroform fraction was the most active with 82.67% sedative effect at 50 and 100 mg/kg i.p. On the other hand,the ethyl acetate and n-butanol fractions displayed significant sedative effects(55.65% and40.87%, respectively) at 100 mg/kg i.p. Among the tested extract/fractions, only chloroform and ethyl acetate fractions showed significant(P < 0.05) muscle relaxant activity in the Rota rod ***: In short, our study provided scientific background to the traditional uses of *** as sedative.

关键词： Diospyros lotus Ebenaceae Sedative Muscle relaxants activity