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Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications 被引量:1
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作者 WANG Xiaohui PENG Li +1 位作者 HUANG Kexin DENG Wei 《Chinese Geographical Science》 SCIE CSCD 2024年第1期1-18,共18页
Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(ex... Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas. 展开更多
关键词 shrinking cities land price propensity score matching(PSM) relative effectiveness China
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THE EARLY RELATIVE BIOLOGICAL EFFECTIVENESS OF SINGLE DOSE OF FAST NEUTRONS(35MeV_(p→Be)) FOR BONE MARROW IN MICE
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作者 孙艳 韩树奎 +4 位作者 徐博 张淑慧 唐景华 常维克 申文江 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1995年第1期71-74,共4页
The early RBE of the bone marrow in mice after studied irradiation with fast neutrons(35 MeVp→Be) was studied.60Co-γ ray was used for referent beams.Using the dos.making 50% loss of the nucleated cells of bone marro... The early RBE of the bone marrow in mice after studied irradiation with fast neutrons(35 MeVp→Be) was studied.60Co-γ ray was used for referent beams.Using the dos.making 50% loss of the nucleated cells of bone marrow in mice relative to control group mice to calculated the RBE value which was 2.13±0.18.Meanwhile,the relationship of the RBE values and the dose of neutrons was noted.On log-log plot the RBE values decrease with increasing dose of fast neutrons and it is consistent with a slope of -0.39± 0.10.The α/β ratios were estimated from linear-quadratic model of cell survival,they are 14.4±1.30 Gy for fast neutrons and 0.83±0.10 Gy for γ-ray,respectively. 展开更多
关键词 Fast neutrons relative biological effectiveness Bone marrow Early reaction.
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The Experimental Measurement of the Relative Biological Effectiveness of Carbon Ions with Different Qualities
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作者 于菊芳 李文建 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期387-390,共4页
The relative biological effectiveness (RBE) of carbon ions with linear energy transfer (LET) of 172 keV/μm and 13.7 keV/μm were determined in this study. The clonogenic survival and premature terminal differenti... The relative biological effectiveness (RBE) of carbon ions with linear energy transfer (LET) of 172 keV/μm and 13.7 keV/μm were determined in this study. The clonogenic survival and premature terminal differentiation were measured on normal human fibroblasts AG01522C and NHDF after exposure of the cells to 250 kV X-rays and carbon ions with different qualities. RBE was determined for these two biological end points. The results showed that the measured RBE10 with a survival fraction of 10% was 3.2 for LET 172 keV/μm, and 1.33 for LET 13.7 keV/μm carbon ions. RBE for a doubling of post-mitotic fibroblasts (PMF) in the population was 2.8 for LET 172 keV/μm, and 1 for LET 13.7 keV/μm carbon ions. For the carbon ion therapy, a high RBE value on the Bragg peak results in a high biological dose on the tumour. The tumour cells can be killed effectively. At the same time, the dose on healthy tissue would be reduced accordingly. This will lighten the late effect such as fibrosis on normal tissue. 展开更多
关键词 carbon ions relative biological effectiveness MEASUREMENT
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Pore structure characteristics of the relative water-resisting layer on the top of the Ordovician in Longgu Coal Mine 被引量:3
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作者 Rong Huren Bai Haibo 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期657-661,共5页
In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture a... In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture and pore structure features of the strata, and identified the main channels which govern the permeability and water-resisting ability of the strata. The permeability of the upper, central and lower strata shows as 2.0504 × 10^-3-2.782762× 10^-3, 4.1092 × 10^-3 -7.3387 × 10^-3 and 2.0891 ×10^-3-3.2705 × 10-3 μm^2, respectively, and porosity of that is 0.6786-0.9197%, 0.3109-0.3951% and 0.9829-1.8655%, respectively. The results indicate that: (I) the main channels of the relative water-resisting layer are the pore throats with a diameter more than 6 μm; (2) the major proportion of pore throats in the vertical flow channel and the permeability first increases and then sharply decreases; (3) the fractures occurring from the top to 20 m in depth of the strata were filled and there occurred almost no fracture under the depth of 40 m; and (4) the ratio of turning point of the main flow channel in the strata on top of Ordovician can be used to confirm the thickness of filled water-resisting lavers. 展开更多
关键词 relative water-resisting layer Filling effect Main channels of seepage Pore structure
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The relative age effect has no influence on match outcome in youth soccer
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作者 Donald T.Kirkendall 《Journal of Sport and Health Science》 SCIE 2014年第4期273-278,共6页
Purpose: In age-restricted youth sport, the over-selection of athletes born in the first quarter of the year and under-selection of athletes born in the last quarter of the year has been called the relative age effe... Purpose: In age-restricted youth sport, the over-selection of athletes born in the first quarter of the year and under-selection of athletes born in the last quarter of the year has been called the relative age effect (RAE). Its existence in youth sports like soccer is well established. Why it occurs has not been identified, however, one thought is that older players, generally taller and heavier, are thought to improve the team's chances of winning. To test this assumption, birth dates and match outcome were correlated to see if teams with the oldest mean age had a systematic advantage against teams with younger mean ages. Methods: Player birth dates and team records (n = 5943 players on 371 teams; both genders; U11-U16) were obtained from the North Carolina Youth Soccer Association for the highest level of statewide youth competition. Results: The presence of an RAE was demonstrated with significant oversampling from players born in the I st vs. the 4th quarter (overall: 29.6% vs. 20.9% respectively, p 〈 0.0001). Mean team age was regressed on match outcomes (winning %, points/match, points/goal, and goals for, against, and goal difference), but there was no evidence of any systematic influence of mean team age and match outcomes, except possibly in U11 males. Conclusion: Selecting players based on physical maturity (and subsequently, on age) does not appear to have any systematic influence on match outcome or season record in youth soccer suggesting that the selection process should be focused on player ability and not on physical maturation. 展开更多
关键词 Match outcomes relative age effect SOCCER Youth sport
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Dependence of epoch-wise two-way nested ANOVA estimates of variances of unmodeled effects present in relative GPS positioning on satellite elevation cutoff angle and PDOP mask
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作者 Darko Andic Radovan Durovic 《Geodesy and Geodynamics》 CSCD 2022年第5期473-491,共19页
Impact of satellite elevation cutoff angle and position dilution of precision(PDOP)mask change on epoch-wise variance components of unmodeled effects that accompany relative Global Positioning System(GPS)positioning i... Impact of satellite elevation cutoff angle and position dilution of precision(PDOP)mask change on epoch-wise variance components of unmodeled effects that accompany relative Global Positioning System(GPS)positioning is presented herein.Data used for this study refer to the winter and summer periods of the years with minimal(2008)and maximal(2013)solar activity.These data were collected every 30 s in static mode,at two permanent GPS stations located in Montenegro,establishing a mediumdistance(116-km-long)baseline with a height difference of approximately 760 m between its endpoints.The study showed that changing satellite elevation cutoff angle,with a fixed PDOP mask,affects epochwise two-way nested ANOVA estimates of variances related to the‘far-field’multipath(considered as the nested factor herein)and the combined unmodeled effect of tropospheric and ionospheric refraction(considered as the nesting factor herein).However,changing of PDOP mask,with a fixed satellite elevation cutoff angle,doesn’t affect epoch-wise two-way nested ANOVA estimate of variance of the combined unmodeled effect of tropospheric and ionospheric refraction,but,generally,affects the estimate of variance of the‘far-field’multipath(possibly mixed with a part of a‘shorter-term’ionospheric refraction),which is especially pronounced for the summer period.It should also be noted that there is a significant influence of satellite elevation cutoff angle change on both epoch-wise horizontal and vertical position accuracy,only for the summer period,especially in the presence of maximal solar activity,while there is no significant impact of PDOP mask change on epoch-wise positional accuracy. 展开更多
关键词 Unmodeled effects in relative GPS positioning 2-way nested ANOVA Epoch-wise variance components Satellite elevation cutoff angle change PDOP mask change
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Response of HD-V2 radiochromic film to argon ions
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作者 Lei Cheng Zhe Zhang +1 位作者 Guiyun Liang Yutong Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期282-286,共5页
A two-dimensional dose detector for ion beam is required in many high energy density physics experiments.As a solid detector,the GAFChromic film offers a good spatial resolution and dosimetric accuracy.For an absolute... A two-dimensional dose detector for ion beam is required in many high energy density physics experiments.As a solid detector,the GAFChromic film offers a good spatial resolution and dosimetric accuracy.For an absolute dose measurement,the relative effectiveness,which represents the darkening efficiency of the film to a radiation source,needs to be taken into consideration.In this contribution,the dose-response of HD-V2 to argon ions is presented for the first time.The calibration was taken over the dose range of 65 Gy-660 Gy with 8-keV argon ions.The response of net optical density is from 0.01 to 0.05.Triple-color dose-response functions are derived.The relative effectiveness for the argon ion beams is about 5%,much lower than that of protons and carbon ions.To explain this effect,the inactivation probability based on track theory of ion bombardment is proposed.Furthermore,a theoretical prediction of the relative effectiveness for single ion is presented,showing the dependence of the darkening efficiency on the atomic number and the incident energy of ions. 展开更多
关键词 radiochromic film DOSIMETRY ion bombardment relative effectiveness
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Sintilimab-induced autoimmune diabetes:A case report and review of the literature 被引量:7
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作者 Jing Yang Ying Wang Xiang-Min Tong 《World Journal of Clinical Cases》 SCIE 2022年第4期1263-1277,共15页
BACKGROUND With the widespread application of immune checkpoint inhibitor(ICI)therapy,the number of immune-related adverse effects(irAEs)has increased over the years.Autoimmune diabetes mellitus(DM)is a rare irAEs of ... BACKGROUND With the widespread application of immune checkpoint inhibitor(ICI)therapy,the number of immune-related adverse effects(irAEs)has increased over the years.Autoimmune diabetes mellitus(DM)is a rare irAEs of ICIs and can be troublesome and life threatening.CASE SUMMARY We report a 78-year-old woman with no history of diabetes who presented with hyperglycemia up to 23.4 mmol/L(random blood glucose level)after 14 courses of sintilimab.Hemoglobin A1c was 8.2%,fasting insulin was 0.29 mIU/mL,and fasting C-peptide was decreased to a level with negative autoantibodies.Combing her medical history and laboratory examination,she was diagnosed with programmed cell death(PD)-1-inhibitor-induced,new-onset autoimmune DM.After controlling her blood glucose,she was treated with daily insulin by subcutaneous injection.She was allowed to continue anti-PD-1 therapy and she still obtained some therapeutic efficacy.We also reviewed some published cases(n=36)of PD-1/PD-ligand 1(PD-L1)inhibitor-induced DM.We also discuss potential pathogenic mechanisms,clinical features,prognostic markers(βcell antibodies,human leukocyte antigen type,PD-L1 Level)of this rare adverse effect.CONCLUSION It is important for all clinicians to be aware of DM as an irAEs of ICIs. 展开更多
关键词 Sintilimab Immune related adverse effects Small cell lung cancer Autoimmune diabetes Case report
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Complex Effective Relative Permittivity of Soil Samples from the Taunus Region (Germany) 被引量:1
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作者 Katja Lauer Christian Albrecht +1 位作者 Christina Salat Peter Felix-Henningsen 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期961-967,共7页
The most important parameter affecting ground-penetrating radar (GPR) measurements is the complex effective relative permittivity εr^*,eff because it controls the propagation velocity and the reflection of GPR pul... The most important parameter affecting ground-penetrating radar (GPR) measurements is the complex effective relative permittivity εr^*,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^*,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^*,eff= εr^*,eff - jεr^*,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^*,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL (1980), we find that Topp et aL's curve tends to underestimate the real part of εr^*,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^*,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^*,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction. 展开更多
关键词 ground-penetrating radar (GPR) complex effective relative permittivity soil sample.
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Tuning Martensitic Phase Transition by Non-Magnetic Atom Vacancy in MnCoGe Alloys and Related Giant Magnetocaloric Effect
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作者 包立夫 黄文登 任亚杰 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期161-164,共4页
The effects of non-magnetic atom vacancy on structural, martensitic phase transitions and the corresponding magnetocMoric effect in MnCoGel-x alloys are investigated using x-ray diffraction and magnetic measurements. ... The effects of non-magnetic atom vacancy on structural, martensitic phase transitions and the corresponding magnetocMoric effect in MnCoGel-x alloys are investigated using x-ray diffraction and magnetic measurements. The introduction of non-magnetic atom vacancy leads to the decrease of the martensitic transition temperature and realizes a temperature window where magnetic and martensitic phase transitions can be tuned together. Moreover, the giant magnetocaloric effect accompanied with the coupled magnetic-structural transition is ob- tained. It is observed that the peak values of magnetic entropy change of MnCoGeo.97 are about -13.9, -35.1 and -47.4J.kg-1K-1 for △H = 2, 5, 7T, respectively. 展开更多
关键词 of on for by Tuning Martensitic Phase Transition by Non-Magnetic Atom Vacancy in MnCoGe Alloys and Related Giant Magnetocaloric Effect in is that
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A NEW METHOD FOR STABILITY ANALYSIS OF UNDERGROUND OPENING USING ARTIFICIAL NEURAL NETWORK
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作者 杨英杰 张清 《Journal of Coal Science & Engineering(China)》 1996年第2期16-22,共7页
The stability of underground opening is strongly constrained by a variety of factors. These include initial stress, structure of rock mass, and underground water, etc. A new approach proposed in this paper aims at rev... The stability of underground opening is strongly constrained by a variety of factors. These include initial stress, structure of rock mass, and underground water, etc. A new approach proposed in this paper aims at revealing the degree of significance of them in order to catch the key factors. This new approach utilizes the mapping potentiality of artificial neural network and works out the sophisticated interactions among those factors from sample set. As a demonstration, an example is given for the application of this method to an underground opening. All results of this paper prove the efficiency of artificial neural network in stability analysis of underground opening. 展开更多
关键词 stability of underground opening artificial neural networks relative Strength of Effect (RSE)
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Community Needs Assessment in Relation to Urban Heat Effects: A Study in Greater Kuala Lumpur, Malaysia
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作者 Li Ping WONG Haridah Alias +1 位作者 Nasrin Aghamohammadi Nik Meriam Nik Sulaiman 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第9期705-711,共7页
Urban areas usually experience higher temperatures compared with their rural surroundings; this is characterized as urban heat islands (UHIs), which are the result of environmental overheating due to anthropic activ... Urban areas usually experience higher temperatures compared with their rural surroundings; this is characterized as urban heat islands (UHIs), which are the result of environmental overheating due to anthropic activities. Urban areas,which are characterised by massive construction that reduce local vegetation coverage, are subject to the absorption of a large amount of solar radiation,which is only partially released into the atmosphere by radiation in the thermal infrared. 展开更多
关键词 A Study in Greater Kuala Lumpur Community Needs Assessment in Relation to Urban Heat Effects MALAYSIA
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Blood and Histopathological Biomarkers of Immune-related Adverse Effects of Treatment with Immune Checkpoint Inhibitors
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作者 Yogesh Jheengut Yi Qian Liu Ling Xiang Liu 《Journal of Nutritional Oncology》 2019年第4期161-171,共11页
Immune checkpoint inhibitors have been a recent major breakthrough in the management of tumors.They have broadened the scope of management in medical oncology,which has been heavily dependent on chemotherapy.Immune ch... Immune checkpoint inhibitors have been a recent major breakthrough in the management of tumors.They have broadened the scope of management in medical oncology,which has been heavily dependent on chemotherapy.Immune checkpoint inhibitors have renewed the hope of many patients for a more effective treatment.However,Immune checkpoint inhibitors are also associated with a variety of adverse effects,most commonly immunerelated adverse events,and these are often different from the known chemotherapy-induced toxicities.Hence,there is a need to identify specific biomarkers which are able to predict or diagnose these immune-related adverse events. 展开更多
关键词 Immune checkpoint inhibitors Immune related adverse effects Cytotoxic T-lymphocyte-associated protein 4 Programmed cell death-1 Programmed death-ligand 1
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Side effects related to groundwater development in urban area
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《Global Geology》 1998年第1期1-2,共2页
关键词 Side effects related to groundwater development in urban area
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Heterogeneous uptake of NO_2 on soils under variable temperature and relative humidity conditions 被引量:3
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作者 Lei Wang Weigang Wang Maofa Ge 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第10期1759-1766,共8页
Heterogeneous reactions of nitrogen dioxide (NO2) on soils collected from Dalian (S 1) and Changsha (S2) were investigated over the relative humidity (RH) range of 5%-80% and temperature range of 278-328 K usi... Heterogeneous reactions of nitrogen dioxide (NO2) on soils collected from Dalian (S 1) and Changsha (S2) were investigated over the relative humidity (RH) range of 5%-80% and temperature range of 278-328 K using a horizontal coated-wall flow tube. The initial uptake coefficients of NO2 on S2 exhibited a decreasing trend from (10 ± 1.3) × 10-8 to (3.1 ± 0.5) x 10-8 with the relative humidity increasing from 5% to 80%. In the temperature effect studies, the initial uptake coefficients of S1 and S2 decreased from (10± 1.2) × 10-8 to (3.8 ± 0.5) × 10-8 and from (16± 2.2) × 10-8 to (3.8 ±0.4) × 10-8 when temperature increased from 278 to 288 K for S1 and from 278 to 308 K for S2, respectively. As the temperature continued to increase, the initial uptake coefficients of S1 and S2 returned to (7.9 ± 1.1)× 10-8 and (20 ± 3.1) × 10-8 at 313 and 328 K, respectively. This study shows that relative humidity could influence the uptake kinetics of NO2 on soil and temperature would impact the heterogeneous chemistry of NO2. 展开更多
关键词 heterogeneous reactions soil particles uptake coefficients temperature dependence relative humidity effect
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Toward a data analytics -based approach for computing and predicting context- sensitive teaching effectiveness
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作者 Kun Tian Ying He +1 位作者 Xiaoran Xu Jiangyang Fu 《Data Science and Informetrics》 2021年第4期26-46,共21页
The traditional student-oriented course evaluation has been the major assessment method on teaching effectiveness worldwide.Useful as it is,it has been widely and continuously criticized for not being a fair,accurate,... The traditional student-oriented course evaluation has been the major assessment method on teaching effectiveness worldwide.Useful as it is,it has been widely and continuously criticized for not being a fair,accurate,and reliable measurement.In search of a more objective assessment method on teaching effectiveness that also reflects the impacts of context-based learning,we propose a theoretical approach from a unique perspective that recognizes teaching effectiveness as a result of the interplays between teacher,student,and context.The approach can be used to compute as well as to predict teaching effectiveness using machine and deep learning technologies,which brings strategical benefits to institutional management.In addition,we install into the approach a mechanism using tokens as incentives to assure the quality of subjective data input.The application framework for the approach is proposed leveraging blockchain.Each implementation of the framework by an establishment is a decentralized application that runs on its chosen blockchain.It is envisioned that the implementations together will form a collective ecology on context-based relative teaching effectiveness,which has the potential to fundamentally impact other academic practices besides teaching effectiveness measurement.The theoretical approach provides a common language to delineate teaching effectiveness from the context-based relative perspective and is customizable during implementation.The teaching effectiveness assessment using the approach downplays the roles played by bias(subjectity)and hence is more objective than that by traditional student-oriented course evaluation. 展开更多
关键词 relative teaching effectiveness Data science application Blockchain Context-based leaming Token economy
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Large electrocaloric effect in BaTiO_3 based multilayer ceramic capacitors 被引量:3
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作者 LU Biao WEN XinHua +8 位作者 TANG ZhenHua LIANG Bo TAO Tao XIE ZhiWei ZHANG TianFu TANG XinGui XIANG Yong LIAO Jie LU ShengGuo 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第7期1054-1058,共5页
The electrocaloric effect(ECE) of multilayer ceramic capacitor(MLCC) of Y5 V type was directly measured via a differential scanning calorimetry(DSC) method and a reference resistor was used to calibrate the heat flow ... The electrocaloric effect(ECE) of multilayer ceramic capacitor(MLCC) of Y5 V type was directly measured via a differential scanning calorimetry(DSC) method and a reference resistor was used to calibrate the heat flow due to the heat dissipation. The results are compared with those calculated from Maxwell relations by using the polarization data obtained from the polarization–electric field hysteresis loops. The direct method shows a larger ECE temperature change, which is accounted for the situation approaches an ideal condition. For the indirect method using Maxwell relations, only the polarization projection along the electric field was taken into account, which will be less than the randomly distributed real polarizations that contribute to the ECE. The MLCCs exhibit a broad peak of ECE around 80 C, which will be favorite for the practical ECE cooling devices. 展开更多
关键词 multilayer ceramic capacitors maxwell relations electrocaloric effect polarization–electric field hysteresis loop differential scanning calorimetry
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Effect of Ag substitution on structural,magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4–x)Ag_xMnO_3 manganites 被引量:4
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作者 R.Thaljaoui M.Pekala +1 位作者 J.-F.Fagnard Ph.Vanderbemden 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第9期875-882,共8页
A systematic investigation on the structural, magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4-x)Ag_xMnO_3(x=0.05 and 0.1) manganites was reported. Rietveld refinements of the X-ray diffraction patterns... A systematic investigation on the structural, magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4-x)Ag_xMnO_3(x=0.05 and 0.1) manganites was reported. Rietveld refinements of the X-ray diffraction patterns confirmed that all samples were single phase and crystallized in the orthorhombic structure with Pnma space group. Magnetic measurements in a magnetic applied field of 0.01T revealed that the ferromagnetic-paramagnetic transition temperature T_C decreased from about 293 to 290 K with increasing silver content from x=0.05 to 0.1. The reported magnetocaloric entropy change and relative cooling power for both samples were considerably remarkable with a △S_(max) value of 1.9 J/(kg·K)and maximum RCP values of 100 J/kg, under a magnetic field change(?μ0H) equal to 1.8T. The analysis of the universal curves gave an evidence of a second order magnetic transition for the studied samples. The magnetic field influence on both the magnetic entropy change and the relative cooling power was also studied and discussed. 展开更多
关键词 monovalent doped manganite XRD SEM ZFC and FC curves mgnetocaloric effect universal curves relative cooling power critical exponents
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Polychlorinated dibenzo-p-dioxins and dibenzofurans and polychlorinated biphenyls in surface soil from the Tibetan Plateau 被引量:2
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作者 Zhenyu Tian Haifeng Li +4 位作者 Huiting Xie Chen Tang Ying Han Mengjing Wang Wenbin Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第10期2041-2047,共7页
Concentrations of Polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) and polychlorinated biphenyls(PCBs) in soil samples from Tibetan Plateau were determined. The average concentration of total 2,3,7,8-P... Concentrations of Polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) and polychlorinated biphenyls(PCBs) in soil samples from Tibetan Plateau were determined. The average concentration of total 2,3,7,8-PCDD/Fs was(2.30 ± 1.02) pg/g, and World Health Organization Toxicity Equivalency(WHO-TEQ) average concentration was(0.013 ± 0.010)pg WHO-TEQ/g. The average concentration of ∑PCBs(7 indicator PCB and 12 dioxin like-PCB congeners) was(16.2 ± 9.25) pg/g, and WHO-TEQ average concentration was 0.043 ±0.049 pg WHO-TEQ/g. Comparing to previous studies in similar environmental conditions,PCDD/Fs and PCBs in this study showed a relatively lower concentration. The altitude dependences of PCDD/Fs and PCBs were also studied. Total organic carbon(TOC) normalized concentrations presented a quadratic relation with the altitudes, and an inflection could be found on the parabola of the total concentrations and some congeners of high concentration.The concentrations decreased with altitudes below about 4500 m above sea level(a.s.l.), while they increased with altitudes above it. These phenomena indicate that cold condensation of PCDD/Fs and PCBs would happen above 4500 m a.s.l, on the Tibetan Plateau. 展开更多
关键词 Cold-trap effect Persistent organic pollutants Indicator polychlorinated biphenyls Inflection Quadratic relation
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Sensitivity of MCF-7 mammosphere CSCs to neutron radiation
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作者 Valentina G.Shuvatova Yuliya P.Semochkina +1 位作者 Alexander N.Strepetov Elizaveta Yu.Moskaleva 《Journal of Cancer Metastasis and Treatment》 2022年第1期28-41,共14页
Aim:Cancer stem cells(CSCs)are highly resistant to chemotherapy andγ-irradiation.Neutrons have a high linear energy transfer,which can lead to extensive damage to the DNA of tumor cells and CSCs.The aim of this work ... Aim:Cancer stem cells(CSCs)are highly resistant to chemotherapy andγ-irradiation.Neutrons have a high linear energy transfer,which can lead to extensive damage to the DNA of tumor cells and CSCs.The aim of this work was to compare the sensitivity of MCF-7 human breast adenocarcinoma cells and CSCs toγ-andγ,n-irradiation.Methods:To increase the number of CSCs,MCF-7 cells were cultured as mammospheres.γ-irradiation was carried out in a GUT-200M device(^(60)Co source)in the dose range of 1-8 Gy at a dose rate of 0.75 Gy/min.γ,n-irradiation was carried out in an IR-8 reactor in the dose range of 0.05-2 Gy at a dose rate of 0.06 Gy/min.DNA DSB formation was assessed by the level ofγH2AX foci using fluorescence microscopy and flow cytometry.CSCs were identified by flow cytometry as CD44^(+)/CD24^(-/low) cells.Results:We showed thatγ,n-irradiation induced the formation ofγH2AX foci of a larger size than didγ-irradiation and led to more severe DNA damage per 1 Gy.Moreover,γ,n-radiation was found to have a high relative biological effectiveness(RBE)as assessed by the cell survival rate,the number of CSCs in culture,and the ability of CSCs to repopulate.The highest RBE of neutron radiation was observed at low doses,when cell survival rate decreased by only 5%-10%.With an increase in the radiation dose,the RBE value decreased for all studied parameters,but it remained as high as 5.Conclusion:γ,n-radiation is highly effective against CSCs.Our results explain the efficacy of neutron therapy for resistant forms of breast cancer. 展开更多
关键词 Cancer stem cells RADIORESISTANCE neutron radiation gamma radiation relative biological effectiveness γH2AX foci mammospheres MCF-7 cells human breast adenocarcinoma
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