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论拉吕埃勒对“Determination-in-the-last-instance”的非哲学阐释 认领 引用
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作者 黄其洪 廖宏伟 《内蒙古师范大学学报（哲学社会科学版）》 2026年第3期105-114,128,共10页
“Determination-in-the-last-instance”的原初含义是“归根到底地决定”,它既是历史唯物主义对经济基础的根本肯定,也是自身的辩证保障。为了忠于具体的历史情境,阿尔都塞使用修辞方法将其发展为“多元决定”的辩证形式。受阿尔都塞... “Determination-in-the-last-instance”的原初含义是“归根到底地决定”,它既是历史唯物主义对经济基础的根本肯定,也是自身的辩证保障。为了忠于具体的历史情境,阿尔都塞使用修辞方法将其发展为“多元决定”的辩证形式。受阿尔都塞的“情境决定论”影响,拉吕埃勒在他的“非哲学”中将“Determination-in-thelast-instance”理解为“最终情态下的决定”,它被视为实在的单边作用机制,并指向一种非思想——世界的可能性未来,这深刻地影响了当代思辨实在论运动中对非人的世界图景的揭示。然而,尽管拉吕埃勒挪用历史唯物主义的概念,并以“非哲学”的方式使其在理论上产生激进的批判效果,但由于它抛弃了在历史唯物主义中原有的社会和历史的维度,导致这一挪用在背离历史唯物主义的同时,也丧失解决现实问题的能力。 展开更多
关键词 Determination-in-the-last-instance 历史唯物主义 拉吕埃勒 非哲学 最终情态下的决定
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Palaeovegetational and palaeoenvironmental changes since the last deglacial in Gonghe Basin, northeast Tibetan Plateau 认领 引用 被引量：34
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作者 CHENG Bo CHEN Fahu ZHANG Jiawu 《Journal of Geographical Sciences》 SCIE CSCD 2013年第1期136-146,共11页
Paleoenvironmental history in the monsoonal margin in the northeast Tibetan Pla- teau provides important clue to the regional climate. Previous researches have been limited by either poor chronology or low resolution.... Paleoenvironmental history in the monsoonal margin in the northeast Tibetan Pla- teau provides important clue to the regional climate. Previous researches have been limited by either poor chronology or low resolution. Here we present a high-resolution pollen record from a 40.92-m-long sediment core （DLH） taken from Dalianhai, a terminal lake situated in the Gonghe Basin, the northeast Tibetan Plateau for reconstructing the vegetation and climate history since the last deglacial on the basis of a chronology controlled by 10 AMS 14C dates on plant remains preserved in the core sediments. The pollen assemblages in DLH core can be partitioned into 6 pollen zones and each zone is mainly characterized by the growth and decline of tree or herb pollen percentage. During the periods of 14.8-12.9 ka and 9.4-3.9 ka, the subalpine arboreal and local herbaceous pollen increased, indicating the subalpine forest developed in the surrounding mountains and a desert steppe or typical steppe developed in Gonghe Basin under a relatively moister climate. During the periods of 15.8-14.8 ka, 12.9-9.4 ka and 3.9-1.4 ka, the forest shrank or disappeared according to different degrees of aridity, and the desert steppe degraded to a more arid steppe desert in the basin, indicating a dry climate. After 1.4 ka, vegetation type around Dalianhai was mainly dominated by steppe suggested by increased Artemisia. Our results suggested the climate history in this region was dry from 15.8-14.8 ka, humid from 14.8-12.9 ka and dry from 12.9-9.4 ka, after which the climate was humid during 9.4-3.9 ka, followed by dry conditions during 3.9-1.4 ka and humid conditions in the last 1.4 ka. The change of pollen percentage and the evolution of palaeovegetation in Dalianhai since the last deglacial were similar to those recorded in Qinghai Lake. The forest expanded in the mountains around Dalianhai during the Bol- ling-Aller^d period, shrank during the Younger Dryas and the early Holocene, then it devel- oped and reached its maximum in the mid-Holocene. During the late Holocene, the vegetation began to shrink till disappearance. However, the timing of forest expansion in the Holocene lagged behind that of Qinghai Lake, and this spatial heterogeneity was probably caused by the different forest species between these two places. The maximum of forest development in the mid-Holocene was inconsistent with the period of stronger summer monsoon in the early Holocene indicated by stalagmite records, the reason might be related to the complexity of vegetation response to a large-scale climatic change. 展开更多
关键词 pollen record Dalianhai last deglacial Holocene palaeovegetation
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Long-lasting phosphorescence study on Y_3Al_5O12 doped with different concentrations of Ce3+ 认领 引用 被引量：12
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作者 张粟 李成宇 +3 位作者 庞然 姜丽宏 师丽丽 苏锵 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第5期426-430,共5页
Long-lasting phosphorescence （LLP） was observed in Ce-doped Y3Al5O12 phosphors synthesized in reducing atmosphere. The characteristic emission of the 2D–2F5/2 and 2D–2F7/2 transition of Ce3＋ in photoluminescence ... Long-lasting phosphorescence （LLP） was observed in Ce-doped Y3Al5O12 phosphors synthesized in reducing atmosphere. The characteristic emission of the 2D–2F5/2 and 2D–2F7/2 transition of Ce3＋ in photoluminescence （PL） and LLP spectra was studied. It was interesting that the ratio between the peak areas of 2D–2F5/2 and 2D–2F 7/2 transitions in the PL spectrum was different from the ratio of that in LLP emission spectrum. And the ratios had different change regularities with increased Ce3＋ concentration. The possible reason was attributed to the defect in the YAG host,which was affected by increasing the Ce3＋ concentration. There were indications that the defect in the Ce3＋-doped YAG samples was strongly associated with oxygen vacancy. And the defect levels were studied through thermoluminescence （TL） experiment. The results showed that the trap depth was between 0.6 and 0.65 eV,and the kinetic order of the LLP was 2. 展开更多
关键词 YAG cerium defects long-lasting phosphorescence rare earths
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A white long-lasting phosphor Y_2O_2S:Tb3+, Sm3+: an improvement of Y_2O_2S:Tb3+ 认领 引用 被引量：5
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作者 林林 陈坤 +4 位作者 王志芳 游宝贵 陈永虎 张慰萍 施朝淑 《Journal of Rare Earths》 SCIE EI CAS 2008年第5期648-651,共4页
As an improvement of reported Y2O2S：Tb^3＋, a white-light long-lasting phosphor： Y2O2S：Tb^3＋, Sm^3＋ was prepared by the solid-state reaction. The photo-luminescence spectra showed that the position and shape of T... As an improvement of reported Y2O2S：Tb^3＋, a white-light long-lasting phosphor： Y2O2S：Tb^3＋, Sm^3＋ was prepared by the solid-state reaction. The photo-luminescence spectra showed that the position and shape of Tb^3＋ and Sm^3＋ emissions under UV excitation were similar in this host, which ensured a stable white emission color （daylight standard of IEC） under different excitations. The decay curves of co-doped samples indicated that the decay times of emissions of the two ions were close. The thermo-luminescence measurement suggested that the traps created by the doped Sm^3＋ ions were helpful to postpone the white afterglow of co-doped samples. Therefore, the function of co-doped Sm^3＋ ions was confirmed as improving the white emission colors of samples and acting as new trap centers. 展开更多
关键词 terbium samarium white long-lasting phosphor rare earths
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Luminescence properties of a new yellow long-lasting phosphorescence phosphor NaAlSiO_4:Eu2+,Ho3+ 认领 引用 被引量：4
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作者 庞然 赵然 +2 位作者 贾永雷 李成宇 苏锵 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第9期792-796,共5页
A new aluminosilicate long-lasting phosphor with composition of NaA1SiO4：Eu2＋,Ho3＋ was synthesized and investigated. Under UV light excitation, the phosphor emitted yellow light corresponding to the characteristic ... A new aluminosilicate long-lasting phosphor with composition of NaA1SiO4：Eu2＋,Ho3＋ was synthesized and investigated. Under UV light excitation, the phosphor emitted yellow light corresponding to the characteristic emission of Eu2＋ due to 5d-4f transi- tion. Bright yellow phosphorescence sustaining for more than 30 rain was observed after ceasing the excitation. The phosphorescence intensity decay obeyed a fl decay law, indicating a tunneling electron-hole recombination process in the phosphor. Four peaks ap- peared in the thermoluminescence curve and the ones at 322 and 370 K were thought to account for the long lasting phosphorescence at room temperature. The Ho3＋ ion incorporated into the phosphor did not give any light but dramatically increased the intensities of both photoluminescence and phosphorescence via promoting defect levels in the phosphor. 展开更多
关键词 NaAlSiO4 luminescence long lasting phosphorescence phosphor rare earths
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Luminescent properties of blue long-lasting phosphorescence phosphors Sr_6Al18Si_2O37:Eu2+,RE3+ 认领 引用 被引量：4
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作者 赵然 庞然 +4 位作者 李海锋 贾永雷 姜丽宏 孙文芝 李成宇 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第9期797-801,共5页
A series of novel blue long-lasting phosphorescence phosphors Sr6A118Si2037：Eu^2＋,RE^3＋ （RE3＋=Ho^3＋, Gd^3＋, Dy^3＋ and Pr^3＋） were prepared by the conventional high-temperature solid-state reaction in a reduc... A series of novel blue long-lasting phosphorescence phosphors Sr6A118Si2037：Eu^2＋,RE^3＋ （RE3＋=Ho^3＋, Gd^3＋, Dy^3＋ and Pr^3＋） were prepared by the conventional high-temperature solid-state reaction in a reductive atmosphere. Their properties were systemati- cally investigated utilizing X-ray diffraction （XRD）, photoluminescence, phosphorescence and thermoluminescence （TL） spectra. The phosphors emitted blue light that was related to the emission of E~＋ due to 5d-4f transition. Bright blue long-lasting phosphorescence （LLP） could be observed after the excitation source was switched off. For the optimized sample, the blue long-lasting phosphores- cence could last for nearly 4 h in the light perception of the dark-adapted human eye （0.32 mcd/m2）. The effects of RE3＋ ions on phosphorescence properties of the phosphors were studied, and the results showed that the co-doping of RE^3＋ ions greatly enhanced the intensity of the peak around 315 K which was related to the long lasting phosphorescence of the phosphors at room temperature and consequently improved the performance of the blue phosphorescence such as intensity and persistent time. 展开更多
关键词 strontium aluminosilicate defects long-lasting phosphorescence luminescence rare earths
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Photo-luminescence properties and thermo-luminescence curve analysis of a new white long-lasting phosphor: Ca_2MgSi_2O_7:Dy3+ 认领 引用 被引量：3
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作者 林林 赵仲华 +2 位作者 张慰萍 郑志强 尹民 《Journal of Rare Earths》 SCIE EI CAS 2009年第5期749-752,共4页
A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen d... A white long-lasting phosphor Ca2MgSi2O7:Dy3+ was prepared by the solid-state reaction. A strong band peaked at 260 nm was shown in the excitation spectrum of 578 nm emission, which might be attributed to the oxygen deficiency of the host. After irradiated with 254 nm for 4 min, the white afterglow of the sample could be seen for 3 h. Moreover, the depths and frequency factors of trap centers were calculated from the thermo-luminescence curve of the sample, which indicated that the trap centers corresponding to the 414 K band were more helpful to the long-lasting phosphorescence. 展开更多
关键词 white long-lasting phosphor silicate dysprosium thermo-luminescence rare earths
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Red long lasting phosphorescence of Eu3+ doped BiOCl semiconducting polycrystals 认领 引用 被引量：3
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作者 周玉婷 宋志国 +6 位作者 李永进 刘群 徐祖元 胡锐 张相周 邱建备 杨正文 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第12期1188-1192,共5页
The exploration of novel long lasting red phosphors is still of importance due to expected commercial applications and scientific interests. In this work, we reported the red long lasting phosphorescence（LLP） from E... The exploration of novel long lasting red phosphors is still of importance due to expected commercial applications and scientific interests. In this work, we reported the red long lasting phosphorescence（LLP） from Eu^3＋ doped BiOCl semiconductor polycrystals. The LLP property of the red phosphor is relatively weak due to less trap density, but the excitation band of LLP stems from the energy gap transition of semiconductor, offering experimental evidence for energy transfer between BiOCl semiconductor and Eu^3＋ ions. Although the afterglow duration of Eu^3＋ doped BiOCl was short temporarily, this work may open a novel kind of red LLP phosphors. 展开更多
关键词 BiOCl red long lasting phosphorescence thermoluminescence rare earths
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ACE、CICARE及LAST护理服务理念在脑梗死患者康复护理中的应用效果 认领 引用 被引量：11
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作者 张燕琴 李晓萍 +1 位作者 孔维维 范东英 《西部中医药》 2019年第11期122-124,共3页
目的:观察ACE、CICARE及LAST护理服务在脑梗死患者康复护理中的应用效果。方法:将脑梗死恢复期患者60例随机分为观察组和对照组各30例。对照组行常规护理,观察组在对照组基础上行ACE、CICARE及LAST护理服务,比较2组患者护理满意度、Bart... 目的:观察ACE、CICARE及LAST护理服务在脑梗死患者康复护理中的应用效果。方法:将脑梗死恢复期患者60例随机分为观察组和对照组各30例。对照组行常规护理,观察组在对照组基础上行ACE、CICARE及LAST护理服务,比较2组患者护理满意度、Barthel指数、护理依从性、回归社会生活信心等心理状况。结果:观察组护理满意度、Barthel指数、护理治疗依从性、对回归社会生活的信心及心理状况优于对照组,差异具有统计学意义(P<0.05)。结论:ACE、CICARE及LAST护理服务有利于提高脑梗死患者临床康复护理满意度,提高患者慢病自我管理能力,增加护理治疗依从性及患者回归社会生活的信心,减少焦虑及抑郁情绪等心理状况的发生。 展开更多
关键词 脑梗死 ACE CICARE LAST 护理服务理念 临床护理
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Characteristics and runoff volume of the Yangtze River paleo-valley at Nanjing reach in the Last Glacial Maximum 认领 引用 被引量：4
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作者 CAO Guangjie WANG Jian +1 位作者 WANG Lingjun LI Yanyan 《Journal of Geographical Sciences》 SCIE 2010年第3期431-440,共10页
The stratigraphical cross-sections of the Yangtze River incised-valley near the No.l, No.3 and No.4 Nanjing Yangtze River bridges were established with respective bore date and documents. By ^14C age analysis of the s... The stratigraphical cross-sections of the Yangtze River incised-valley near the No.l, No.3 and No.4 Nanjing Yangtze River bridges were established with respective bore date and documents. By ^14C age analysis of the samples of four drilling cores near the No.4 Bridge （to be built）, we can find that the time range of paleo-valley is dated in the LGM at a depth of-60 m to -90 m near Nanjing. It is also indicated that the deep incised-valley channel was narrow and the river flowed swiftly. The ancient Yangtze River deep channel presented partially and deeply incised features near the No.1 Bridge. According to previous publications, much research has been done on the main paleo-channel of the Yangtze River, but few results have been achieved on discharge estimation. In this paper, the incipient velocity and average veIocity of the LGM was calculated with Vc=4.60d^1/3h^1/6, Vc=1.281g（ 13.15. h /d95） √gd, V≈6.5u＊｜h/d90｜^1/6 etc., in terms of the river shape, sedimentary grain size and sequences near the No.3 and No.1 bridges. Moreover, the discharge in Nanjing reach of the Yangtze River during the LGM has been estimated to be around 12,000-16,000 m^3/s according to the relationship of discharge, velocity of flow and cross-section. 展开更多
关键词 the Last Glacial Maximum Nanjing reach of the Yangtze River paleo-valley velocity of flow runoff volume
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Characteristics of Temperature Change in China over the Last 2000 years and Spatial Patterns of Dryness/Wetness during Cold and Warm Periods 认领 引用 被引量：17
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作者 Quansheng GE Haolong LIU +2 位作者 Xiang MA Jingyun ZHENG Zhixin HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第8期941-951,共11页
This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation ... This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃（100 yr）^（-1）; however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern： dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China. 展开更多
关键词 temperature change dry-wet spatial pattern cold and warm periods last 2000 years China
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Regional-scale Surface Air Temperature and East Asian Summer Monsoon Changes during the Last Millennium Simulated by the FGOALS-gl Climate System Model 认领 引用 被引量：12
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作者 MAN Wenmin ZHOU Tianjun 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第4期765-778,共14页
The spatial patterns and regional-scale surface air temperature （SAT） changes during the last millennium,as well as the variability of the East Asian summer monsoon （EASM） were simulated with a low-resolution vers... The spatial patterns and regional-scale surface air temperature （SAT） changes during the last millennium,as well as the variability of the East Asian summer monsoon （EASM） were simulated with a low-resolution version of Flexible Global Ocean-Atmosphere-Land-Sea-ice （FGOALS-gl） model.The model was driven by both natural and anthropogenic forcing agents.Major features of the simulated past millennial Northern Hemisphere （NH） mean SAT variations,including the Medieval Climate Anomaly （MCA）,the Little Ice Age （LIA） and the 20th Century Warming （20CW）,were generally consistent with the reconstructions.The simulated MCA showed a global cooling pattern with reference to the 1961-90 mean conditions,indicating the 20CW to be unprecedented over the last millennium in the simulation.The LIA was characterized by pronounced coldness over the continental extratropical NH in both the reconstruction and the simulation.The simulated global mean SAT difference between the MCA and LIA was 0.14°C,with enhanced warming over high-latitude NH continental regions.Consistencies between the simulation and the reconstruction on regional scales were lower than those on hemispheric scales.The major features agreed well between the simulated and reconstructed SAT variations over the Chinese domain,despite some inconsistency in details among different reconstructions.The EASM circulation during the MCA was stronger than that during the LIA The corresponding rainfall anomalies exhibited excessive rainfall in the north but deficient rainfall in the south.Both the zonal and meridional thermal contrast were enhanced during the MCA.This temperature anomaly pattern favored a stronger monsoon circulation. 展开更多
关键词 last millennium surface air temperature spatial patterns regional-scale variation East Asian summer monsoon
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Phosphorescence properties and energy transfer of red long-lasting phosphorescent(LLP) material β-Zn_3(PO_4)_2:Mn2+,Pr3+ 认领 引用 被引量：2
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作者 谢婷 郭鸿旭 +5 位作者 张俊英 Christopher Odetola 何裕能 林珩 陈国良 郑子山 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第10期1056-1063,共8页
The red long-lasting phosphorescent （LLP） of β-Zn3（POa）2：Mn2＋,pr3＋ material was prepared through combustion and conventional solid-state sintering methods. The influence of Pr3＋ ions on luminescence and LLP o... The red long-lasting phosphorescent （LLP） of β-Zn3（POa）2：Mn2＋,pr3＋ material was prepared through combustion and conventional solid-state sintering methods. The influence of Pr3＋ ions on luminescence and LLP of Mn2＋ in 13-Zn3（POa）2：Mn2＋,pr3＋ phosphor was systematically investigated. The phosphor presented a strong photoluminescence peak at 620 nm attributed to the 4T1g→ 6A1 g transition of Mn2＋ ions in octahedral coordination. Red LLP was observed in β-Zn3（PO4）2：Mn2＋,Pr3＋ phosphors with persistence time for more than 2 h. It was found that the long persistent phosphorescent performance of Mn2＋ such as brightness and duration was improved by the energy transfer from Pr3＋ to Mn2＋ when Pr3＋ ions as sensitizers were doped into matrix. The fact that the TL peak at low temperature was largely enhanced in Mn2＋, Pr3＋ codoped ^-Zn3（PO4）2 phosphor showed the significant increase of defect concentration with suitable depth. There existed two factors working together to be responsible for the enhancement of LLP performance in β-Zn3（PO4）2：Mn2＋,Pr3＋. 展开更多
关键词 long-lasting phosphorescent energy transfer Zn3（PO4）2 rare earths
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Characterization of Y_2O_2S∶Eu 3+, Mg2+, Ti4+ Long-Lasting Phosphor Synthesized by Flux Method 认领 引用 被引量：11
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作者 王育华 王治龙 《Journal of Rare Earths》 SCIE EI CAS 2006年第1期25-28,共4页
Long-lasting phosphor Y2O2S ： Eu^3＋ , Mg^2＋ , Ti^4＋ was synthesized by a flux method and their luminescence properties were investigated. The result indicates that the unit cell parameter c is linearly increased w... Long-lasting phosphor Y2O2S ： Eu^3＋ , Mg^2＋ , Ti^4＋ was synthesized by a flux method and their luminescence properties were investigated. The result indicates that the unit cell parameter c is linearly increased with the increase of Eu2O3 content in Y2O2S： Eu^3＋ （0.01 ≤ x ≤0.10）. On the other hand, the change of unit cell parameter a is not linear dependence. In the Y2O2S： Eu^3 ＋ crystal structure, Eu^3＋ ions only replaced Y^3 ＋ ions＇ places in which it posited center position of c axis. With the increase of Eu2O3 content, the position of the strongest emission peak changed from 540 nm （5D1→^ 7F2 transition） to 626 nm （^5Do→^7TF2 transition）, and the maximum intensity was obtained when x = 0.09 in Y2O2S： Eu^3＋ （0.01 ≤x ≤0.10）. This is due to the environment of trivalent europium in the crystal structure of Y2O2S. Doping with Mg^2＋ or Ti^4＋. ions alone cannot get the good long-lasting afterglow effect, whereas co-doping with Mg^2 ＋ and Ti^4 ＋ ions and excited with 365 nm ultraviolet light, a strong thermoluminesence peak appeared, red and orange long-lasting phosphorescence （LLP） was also observed and the phosphorescence lasted nearly 3 h in the light perception of the dark-adapted human eye （0.32 mcd·m^-2）. Thus the LLP mechanism was analyzed. 展开更多
关键词 Y2O2S： Eu^3 ＋ , Mg^2 ＋ , Ti^4 ＋ flux method long-lasting phosphorescence material rare earths
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Coincidence of abandoned settlements and climate change in the Xinjiang oases zone during the last 2000 years 认领 引用 被引量：4
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作者 JIA Dan FANG Xiuqi ZHANG Chengpeng 《Journal of Geographical Sciences》 SCIE CSCD 2017年第9期1100-1110,共11页
The study on the relationship of abandoned settlements and climate change in the oases could provide a historical reference for understanding human responses to present and future global warming in the arid zone. A to... The study on the relationship of abandoned settlements and climate change in the oases could provide a historical reference for understanding human responses to present and future global warming in the arid zone. A total of 554 abandoned historical settlements in Xinjiang Uygur Autonomous Region, China, were used to examine the relationship between abandoned settlements and temperature change over the past 2000 years. The analysis covered dynastic epochs from the Han Dynasty （206BC-220AD） to the Qing Dynasty （1644AD- 1911AD） in the oases of Xinjiang. Greater density of settlements was found at the oases larger than 2000 km^2, which were more stable and less sensitive to climate change compared to smaller oases. Settlements flourished at small oases and the middle and lower reaches of rivers during warm periods and shrank back to piedmont basins and upstream alluvial fans during cold periods. These results demonstrated responses of oasis agriculture to climate change. 展开更多
关键词 abandoned settlements climate change oasis Xinjiang the last 2000 years
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Preparation of Long-Lasting Phosphorescence (LLP) Glass-Ceramic Materials 认领 引用 被引量：2
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作者 李成宇 苏锵 王淑彬 《Journal of Rare Earths》 SCIE EI CAS 2004年第1期67-69,共3页
Three kinds of glass-ceramics, i.e., Mn 2+ doped zinc borosilicate, Eu 2+, Dy 3+ co-doped strontium aluminoborate and Eu 2+, Nd 3+ co-doped calcium aluminoborate were prepared, whose phosphorescence emission band peak... Three kinds of glass-ceramics, i.e., Mn 2+ doped zinc borosilicate, Eu 2+, Dy 3+ co-doped strontium aluminoborate and Eu 2+, Nd 3+ co-doped calcium aluminoborate were prepared, whose phosphorescence emission band peaks at 525, 516 and 464 nm, respectively. In preparation of these glass-ceramics the base glasses were gained by heating the mixed starting materials at high temperature to get the transparent glasses; then those glasses were heat-treated and turned to opaque glass-ceramics. X-ray diffraction (XRD) shows that the crystallites are ZnSiO 4, SrAl 2O 4 and α-CaAl 2B 2O 7, respectively. It is a useful way to get new LLP materials by the method reported in this work that may be considered as “from glass to crystal”. 展开更多
关键词 optics luminescence glass-ceramic heat-treatment long-lasting phosphorescence rare earths
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The Southern Annular Mode(SAM) in PMIP2 Simulations of the Last Glacial Maximum 认领 引用 被引量：1
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作者 Seong-Joong KIM L Junmei Baek-Min KIM 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第4期863-878,共16页
The increasing trend of the Southern Annular Mode （SAM） in recent decades has influenced climate change in the Southem Hemisphere （SH）.How the SAM will respond increased greenhouse gas concentrations in the future... The increasing trend of the Southern Annular Mode （SAM） in recent decades has influenced climate change in the Southem Hemisphere （SH）.How the SAM will respond increased greenhouse gas concentrations in the future remains uncertain.Understanding the variability of the SAM in the past under a colder climate such as during the Last Glacial Maximum （LGM） might provide some understanding of the response of the SAM under a future warmer climate.We analyzed the changes in the SAM during the LGM in comparison to pre-industrial （PI） simulations using five coupled ocean-atmosphere models （CCSM,FGOALS,IPSL,MIROC,HadCM） from the second phase of the Paleoclimate Modelling Intercomparison Project （PMIP2）.In CCSM,MIROC,IPSL,and FGOALS,the variability of the simulated SAM appears to be reduced in the LGM compared to the PI simulations,with a decrease in the standard deviation of the SAM index.Overall,four out of the five models suggest a weaker SAM amplitude in the LGM consistent with a weaker SH polar vortex and westerly winds found in some proxy records and model analyses.The weakening of the SAM in the LGM was associated with an increase in the vertical propagation of Rossby waves in southern high latitudes. 展开更多
关键词 Southern Annular Mode Last Glacial Maximum PMIP2 Southern Hemisphere westerly winds
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Interannual Climate Variability Change during the Medieval Climate Anomaly and Little Ice Age in PMIP3 Last Millennium Simulations 认领 引用 被引量：6
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作者 Kaiqing YANG Dabang JIANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期497-508,共12页
In this study, we analyzed numerical experiments undertaken by 10 climate models participating in PMIP3（Paleoclimate Modelling Intercomparison Project Phase 3） to examine the changes in interannual temperature varia... In this study, we analyzed numerical experiments undertaken by 10 climate models participating in PMIP3（Paleoclimate Modelling Intercomparison Project Phase 3） to examine the changes in interannual temperature variability and coefficient of variation（CV） of interannual precipitation in the warm period of the Medieval Climate Anomaly（MCA） and the cold period of the Little Ice Age（LIA）. With respect to the past millennium period, the MCA temperature variability decreases by 2.0% on average over the globe, and most of the decreases occur in low latitudes. In the LIA, temperature variability increases by a global average of 0.6%, which occurs primarily in the high latitudes of Eurasia and the western Pacific. For the CV of interannual precipitation, regional-scale changes are more significant than changes at the global scale, with a pattern of increased（decreased） CV in the midlatitudes of Eurasia and the northwestern Pacific in the MCA（LIA）. The CV change ranges from-7.0% to 4.3%（from -6.3% to 5.4%）, with a global average of -0.5%（-0.07%） in the MCA（LIA）.Also, the variability changes are considerably larger in December–January–February with respect to both temperature and precipitation. 展开更多
关键词 interannual variability last millennium Medieval Climate Anomaly Little Ice Age
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Winter and summer monsoonal evolution in Gonghe Basin, northeastern Qinghai-Tibetan Plateau since the Last Glacial Maximum 认领 引用 被引量：1
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作者 Bing Liu HeLing Jin +2 位作者 Zhong Sun ZhiZhu Su CaiXia Zhang 《Research in Cold and Arid Regions》 CSCD 2013年第3期282-292,共11页
Geochemical and grain size analysis on the DQ （Dongqi） profile from Gonghe Basin, northeastern Qinghai-Tibetan Plateau, indi- cates that regional climate has experienced several cold-dry and warm-wet cycles since th... Geochemical and grain size analysis on the DQ （Dongqi） profile from Gonghe Basin, northeastern Qinghai-Tibetan Plateau, indi- cates that regional climate has experienced several cold-dry and warm-wet cycles since the last glacial maximum （LGM）. The cold and dry climate dominated the region before 15.82 cal. ka B.E due to stronger winter monsoon and weaker summer monsoon, but the climate was relatively cold and wetter prior to 21 cal. ka B.E. In 15.824.5 cal. ka B.E, summer monsoon strength in- creased and winter monsoon tended to be weaker, implying an obvious warm climate. Specifically, the relatively cold and dry condition appeared in 14.7-13.7 cal. ka B.E and 12.14.5 cal. ka B.R, respectively, while relatively warm and wet in 13.~12.1 cal. ka B.E. The winter and summer monsoonal strength presents frequent fluctuations in the Holocene and relatively warm and wet conditions emerged in 9.5~.0 cal. ka B.E due to stronger summer monsoon. From 7.0 to 5.1 cal. ka B.E, the cycle of cold-dry and warm-wet climate corresponds to frequent fluctuations of winter and summer monsoons. The climate becomes warm and wet in 5.1 2.7 cal. ka B.E, accompanying increased summer monsoon, but it tends to be cold and dry since 2.7 cal. ka B.R due to en- hanced winter monsoonal strength. In addition, the evolution of regional winter and summer monsoons is coincident with warm and cold records from the polar ice core. In other words, climatic change in the Gonghe Basin can be considered as a regional re- sponse to global climate change. 展开更多
关键词 last glacial maximum period Gonghe Basin aeolian deposits winter and summer monsoonal evolution
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Climate change comparison between Arctic and other areas in the Northern Hemisphere since the last Interstade 认领 引用
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作者 XU Juan WANG Guo ZHANG Baiping 《Journal of Geographical Sciences》 SCIE 2007年第1期43-50,共8页
Based on temperature reconstruction and proxy data from 14 sites in the Northern Hemisphere, this paper focused on comparing the cycles of temperature variations between the Arctic and other areas, including Atlantic,... Based on temperature reconstruction and proxy data from 14 sites in the Northern Hemisphere, this paper focused on comparing the cycles of temperature variations between the Arctic and other areas, including Atlantic, Europe, China, Asia, Pacific, Indian Ocean, and America during the transition from the last Interstade to the Last Glacial Maximum, from the Last Glacial Maximum to megathermal period in Holocene and the transition of the Little Ice Age （LIA） by the methods of Singular Spectrum Analysis （SSA） and Maximum Entropy Spectrum （MES）. The results showed that environmental changes in the Arctic are most similar to that in the North American and better similar to Asia, Atlantic and Pacific, the least similar to Indian Ocean and Europe. The 1500-year oscillation of temperature existed both in Arctic and Europe. 展开更多
关键词 climatic cycles comparison Arctic Northern Hemisphere last Interstade
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