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10篇 您的检索式:作者名="Ren Qingfeng"
    题名 作者 年代 出处 被引量
1Holocene vegetational and climatic variation in westerly-dominated areas of Central Asia inferred from the Sayram Lake in northern Xinjiang,China显示文摘Changes in the vegetation and climate of the westerly-dominated areas in Central Asia during the Holocene were interpreted using pollen-assemblages and charcoal data from a 300-cm-long sediment core of the Sayram Lake,northern Xinjiang.Accele-rator Mass Spectrometry(AMS) radiocarbon dating methods were applied to bulk organic matter of the samples.Artemisia spp./Chenopodiaceae ratios and results from principal component analysis were used to infer that the lake basin was dominated by desert vegetation before ca.9.6 cal.ka BP,which suggests a warm and dry climate in the early Holocene.Desert steppe/steppe expanded during 9.6-5.5 cal.ka BP,indicating a remarkable increase both in the precipitation and temperature during the mid-Holocene.Desert vegetation dominated between 6.5 and 5.5 cal.ka BP,marking an extreme warmer and drier interval.The steppe/meadow steppe recovered,and temperatures decreased from 5.5 cal.ka BP in the late Holocene,as indicated by the increased abundance of Artemisia and the development of meadows.Holocene temperatures and moisture variations in the Sayram Lake areas were similar to those of adjacent areas.This consistency implies that solar radiation was the main driving factor for regional temperature changes,and that the effect of temperature variations was significant on regional changes in humidity.The evolution of climate and environment in the Sayram Lake areas,which were characterized as dry in the early Holocene and relatively humid in the middle-late Holocene,are clearly different from those in monsoonal areas.Dry conditions in the early Holocene in the Sayram Lake areas were closely related to decreased water vapor advection.These conditions were a result of reduced westerly wind speeds and less evaporation upstream,which in turn were caused by seasonal changes in solar radiation superimposed by strong evaporation following warming and drying local climate.JIANG QingFeng JI JunFeng SHEN Ji Ryo MATSUMOTO TONG GuoBang QIAN Peng REN XueMei YAN DeZhi 2013Science China Earth Sciences2013,56,3:32
2Single W18O49 nanowires: A multifunctional nanoplatform for computed tomography imaging and photothermal/ photodynamic/radiation synergistic cancer therapy显示文摘联合治疗是通常基于复杂 nanostructures 的利用,多重部件为 photothermal 作为相片热的精力变换器, photo-sensitizers,或剂量 intensifiers 工作的有希望的癌症治疗策略治疗(PTT ) ,光力学的治疗(太平洋夏季时间) ,或放射治疗(RT ) 。在这研究, ultrathin 钨氧化物 nanowires (W 18 O 49) 用一条 solvothermal 途径被综合并且作为多功能的 theranostic nanoplatform 检验了。在 vitro 并且在 vivo,分析证明这些 nanowires 能导致广泛的热 -- 并且汗衫在 980 nm 在附近下面的癌症房间的调停氧的损坏红外线(NIR ) 激光刺激。他们也被显示作为加强在放射治疗期间局部地并且有选择地提高放热精力免职的代理人的放射剂量工作。独自比作导致 NIR 的 PTT/PDT 和 RT, W 18 O 49-based synergistic tri 形式的治疗根除了异种皮移植肿瘤和没有复发被观察在以内一 9 月列在后面起来。而且,钨元素的强壮的 X 光检查变细能力(Z = 74, 4.438 厘米 2????  ??  ?? 佦 ? 畳 ?? 猯扵 ̄??Jianjian Qiu Qingfeng Xiao Xiangpeng Zheng Libo Zhang Huaiyong Xing Dalong Ni Yanyan Liu Shengjian Zhang Qingguo Ren Yanqing Hua Kuaile Zhao Wenbo Bu 2015Nano Research2015,8,11:5
3Superior performance and high service stability for Ge Te-based thermoelectric compounds显示文摘GeTe-based compounds have been intensively studied recently due to their superior thermoelectric performance,but their real applications are still limited so far due to the drastic volume variation that occurs during the rhombohedral–cubic phase transition,which may break the material or the material/electrode interface during service.Here,superior performance and high service stability for GeTe-based thermoelectric compounds are achieved by co-doping Mg and Sb into GeTe.The linear coefficient of thermal expansion before phase transition is greatly improved to match that after phase transition,yielding smooth volume variation around the phase transition temperature.Likewise,co-doping(Mg,Sb)in GeTe successfully tunes the carrier concentration to the optimal range and effectively suppresses the lattice thermal conductivity.A peak z T of 1.84 at 800 K and an average z T of 1.2 in 300–800 K have been achieved in Ge0.85Mg0.05Sb0.1Te.Finally,a Ni/Ti/Ge0.85Mg0.05Sb0.1Te thermoelectric uni-leg is fabricated and tested,showing quite good service stability even after 450 thermal cycles between 473 K and 800 K.This study will accelerate the application of GeTe-based compounds for power generation in the mid-temperature range.Tong Xing Qingfeng Song Pengfei Qiu Qihao Zhang Xugui Xia Jincheng Liao Ruiheng Liu Hui Huang Jiong Yang Shengqiang Bai Dudi Ren Xun Shi Lidong Chen 2019National Science Review2019,6,5:4
4Contents Variation Analysis ofγ-Amino Butyric Acid in Semen sojae praeparatum Fermentation Using Online Pre-Column Derivatization-HPLC显示文摘This paper reported the contents variation analysis ofγ-amino butyric acid(GABA)in Semen sojae praeparatum(SSP)which is a famous traditional Chinese medicine.High performance liquid chromatography(HPLC)was used and GABA was derivatized by online pre-column derivatization with o-phthalaldehyde(OPA).To validate this method,the precision,stability,repeatability and recovery were discussed.In the concentration range from 0.0125 to 0.400 mg/m L,the calibration curve for GABA was linear and the regression equation was obtained with correlation coefficient(R2)of 0.9999.Relatively high levels of GABA exist in SSP and the content changes of GABA at different time points during the fermenting process were detected.At the'yellow cladding'stage,GABA level was very low or even undetectable;the'secondary fermentation'stage witnessed a rapid increase of GABA content to 1.39-5.52 mg/g,which remained stable after 18 days of'secondary fermentation'.This study demonstrated that GABA was generated at the'secondary fermentation'stage,revealing the significance and rationality of the'secondary fermentation'stage in the fermenting process of SSP.On the other hand,it suggested the downside of taking soy isoflavones as the only measurement in existing quality assessment and optimization approach for the fermenting process of SSP.WENG Meizhi HE Jing REN Jiaxiu LIANG Yonghong CHEN Qingfeng SU Mingsheng WANG Liyuan XIE Xiaomei 2021Wuhan University Journal of Natural Sciences2021,26,1:2
5Structural, elastic and electronic properties of transition metal carbides TMC (TM=Ti, Zr, Hf and Ta) from first-principles calculations显示文摘Hui Li Litong Zhang Qingfeng Zeng Kang Guan Kaiyuan Li Haitao Ren Shanhua Liu Laifei Cheng 2011Solid State Communications2011,,8:1
6A joint call for actions to advance taxonomy in China显示文摘Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in China exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in China.Chaodong Zhu Arong Luo Ming Bai Michael COrr Zhonge Hou Siqin Ge Jun Chen Yibo Hu Xuming Zhou Gexia Qiao Hongzhi Kong Limin Lu Xiaohua Jin Lei Cai Xinli Wei Ruilin Zhao Wei Miao Qingfeng Wang Zhongli Sha Qiang Lin Meng Qu Jianping Jiang Jiatang Li Jing Che Xuelong Jiang Xiaoyong Chen Lianming Gao Zongxin Ren Chunlei Xiang Shixiao Luo Donghui Wu Dong Liu Yanqiong Peng Tao Su Chenyang Cai Tianqi Zhu Wanzhi Cai Xingyue Liu Hu Li Huaijun Xue Zhen Ye Xuexin Chen Pu Tang Shujun Wei Hong Pang Qiang Xie Feng Zhang Feng Zhang Xianjin Peng Aibing Zhang Taiping Gao Changfa Zhou Chen Shao Libin Ma Zhaoming Wei Yunxia Luan Ziwei Yin Wu Dai Cong Wei Xiaolei Huang Jingxian Liu Xiangsheng Chen Tianci Yi Zhisheng Zhang Zhulidezi Aishan Qin Li Hongying Hu 2022Zoological Systematics2022,47,3:1
7Promoting near-infrared photocatalytic activity of carbon-doped carbon nitride via solid alkali activation显示文摘Ultrabroad spectral absorption is required for semiconductor photocatalysts utilized for solar-to-chemical energy conversion.The light response range can be extended by element doping,but the photocatalytic performance is generally not enhanced correspondingly.Here we present a solid alkali activation strategy to synthesize near-infrared(NIR)light-activated carbon-doped polymeric carbon nitride(A-cPCN)by combining the copolymerization of melamine and 1,3,5-trimesic acid.The prepared A-cPCN is highly crystalline with a narrowed bandgap and enhanced efficiency in the separation of photogenerated electrons and holes.Under irradiation with NIR light(780 nm≥λ≥700 nm),A-cPCN shows an excellent photocatalytic activity for H_(2)generation from water with rate of 165µmol g^(−1)h^(−1),and the photo-redox activity for H_(2)O_(2)production(109µmol g^(−1)h^(−1))from H_(2)O and O_(2),whereas no observed photocatalytic activity over pure PCN.The NIR photocatalytic activity is due to carbon doping,which leads to the formation of an interband level,and the alkali activation that achieved shrinking the transfer distance of photocarriers.The current synergistic strategy may open insights to fabricate other carbon-nitrogen-based photocatalysts for enhanced solar energy capture and conversion.Qingfeng Li Can Ren Chuntian Qiu Tingchao He Qitao Zhang Xiang Ling Yangsen Xu Chenliang Su 2021Chinese Chemical Letters2021,32,11:1
8Fiber Bragg grating and its application in external cavity semiconductor laser显示文摘Lili Wang Jianhua Ren Hongguang Li Tonggang Zhao Qingfeng Xu Xinhua Chang Lingling Zhao 2012Optik - International Journal for Light and Electron Optics2012,,:1
9AN APPROACH TO THE ECOAGRICULTURAL CONSTRUCTION IN BAICHA VILLAGE OF PENGYANG COUNTY,NINGXIA显示文摘Agricultural production activities are organic combinations between the courses of nat-ural reproduction and economic one. Natural reproduction course is the material base forthe agro-ecological and economic system uniformly operating. So the development ofagro-production has closely concerned with the ecological circumstances. The serious wat-Xie Yingzhong Ren Qingfeng Ma Gaoyun Ningxia Agricultural College 1993干旱区资源与环境1993,7,Z1:0
10替莫唑胺联合利妥昔单抗对复发的老年原发中枢神经淋巴瘤的应用(英文)显示文摘Objective: The aim of our study was to analyze the long-term results of rituximab combined with temozolomide in treatment of elderly patients (> 60 years) with relapsed primary central nervous system lymphoma (PCNSL). Methods: Twelve postoperative elderly patients (> 60 years) were treated between August 2004 and October 2009. Temozolomide 100 mg/m2 to 200 mg/m2 days 1 to 7 and 15 to 21 and rituximab 375 mg/m2 days 1, 5, 8, 22. The maximum number of rituximab cycles was two. After one or two cycles of this combination, patients with an objective response and an acceptable level of toxicity continued treatment with single agent temozolomide (days 1 to 5, every 28 days). The overall survival was analyzed by using Kaplan-Meier. Results: The overall survival was 9 months. Toxicity was very mild with no grade 3-4 neurotoxicity toxic events. Conclusion: Rituximab combined with temozolomide seems to yields substantial long-term survival with moderate toxicity for the treatment of elderly relapsed PCNSL.Qingfeng Li Gang Wu Zhihua Sun Jinghua Ren 2011The Chinese-German Journal of Clinical Oncology2011,10,7:0
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