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| 1 | Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future. | Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang | 2020 | National Science Review2020,7,8: | 51 |
| 2 | Three-dimensional graphene networks: synthesis,properties and applications显示文摘Recently, three-dimensional graphene/graphene oxide(GO) networks(3DGNs) in the form of foams,sponges and aerogels have atracted much atention. 3D structures provide graphene materials with high speciic surface areas, large pore volumes, strong mechanical strengths and fast mass and electron transport,owing to the combination of the 3D porous structures and the excellent intrinsic properties of graphene.his review focuses on the latest advances in the preparation, properties and potential applications of 3D micro-/nano-architectures made of graphene/GO-based networks, with emphasis on graphene foams and sponges. | Yanfeng Ma Yongsheng Chen | 2015 | National Science Review2015,2,1: | 37 |
| 3 | Influence of Atmospheric Particulate Matter on Ozone in Nanjing,China:Observational Study and Mechanistic Analysis显示文摘Particulate matter with diameters of 2.5 μm or smaller(PM_(2.5)) and ozone(O_3) are major pollutants in the urban atmosphere. PM_(2.5) can affect O_3 by altering the photolysis rate and heterogeneous reactions. However, these two processes and their relative importance remain uncertain. In this paper, with Nanjing in China as the target city, we investigate the characteristics and mechanism of interactions between particles and O_3 based on ground observations and numerical modeling.In 2008, the average concentrations of PM_(2.5) and O_3 at Caochangmen station are 64.6 ± 47.4 μg m^(-3) and 24.6 ± 22.8 ppb,respectively, while at Pukou station they are 94.1 ± 63.4 μg m^(-3) and 16.9 ± 14.9 ppb. The correlation coefficient between PM_(2.5) and O_3 is -0.46. In order to understand the reaction between PM_(2.5) and O_3, we construct a box model, in which an aerosol optical property model, ultraviolet radiation model, gas phase chemistry model, and heterogeneous chemistry model,are coupled. The model is employed to investigate the relative contribution of the aforementioned two processes, which vary under different particle concentrations, scattering capability and VOCs/NOxratios(VOCs: volatile organic compounds;NOx: nitric oxide and nitrogen dioxide). Generally, photolysis rate effect can cause a greater O_3 reduction when the particle concentrations are higher, while heterogeneous reactions dominate O_3 reduction with low-level particle concentrations.Moreover, in typical VOC-sensitive regions, O_3 can even be increased by heterogeneous reactions. In Nanjing, both processes lead to O_3 reduction, and photolysis rate effect is dominant. Our study underscores the importance of photolysis rate effect and heterogeneous reactions for O_3, and such interaction processes should be fully considered in future atmospheric chemistry modeling. | Yawei QU Tijian WANG Yanfeng CAI Shekou WANG Pulong CHEN Shu LI Mengmeng LI Cheng YUAN Jing WANG Shaocai XU | 2018 | Advances in Atmospheric Sciences2018,35,11: | 33 |
| 4 | Effect of nitrification inhibitor DMPP on nitrogen leaching, nitrifying organisms, and enzyme activities in a rice-oilseed rape cropping system显示文摘DMPP (3,4-dimethylpyrazole 磷酸盐) 被用来从沥滤或脱氮减少氮(N) 损失并且在农业土地改进 N 供应。然而,它使涉及 N 的有机体和酶活动硝化骑车的土壤上的影响大部分是未知的。因此,为二年,一个在农场上实验被进行了,到阐明矿物质 N 上的 DMPP 的效果(NH4+- N 和 NO3 ? 在 rice-oilseed 的沥滤的 -N) ,使硝化的有机体,和从的酶强奸收割系统。独自包括脲的三个处理(UA ) ,脲 +1% DMPP (DP ) ,和没有化肥(CK ) ,被执行了。结果证明那 DP 提高了吝啬的 NH4+-N 集中由 19.1%24.3% ,但是减少了吝啬的 NO3 ?-N 集中由 44.9%56.6% 在 leach 吃了在二年的大米强奸旋转下面,与 UA 处理相比。氧化的氨的人口细菌,硝酸盐还原酶的活动,和在 DP 处理的亚硝酸根 reductase 减少了大约 24.5%30.9% , 14.9%43.5% ,和 14.7%31.6% ,分别地作为与 UA 处理相比。然而,亚硝酸根氧化细菌和氢氧根胺 reductase 由 DMPP 仍然保持几乎未受影响。DMPP 有潜力也减少 NO3,这被建议 ?-N 由从脱氮禁止氨氧化或 N 损失沥滤,它赞成在 rice-oilseed 的 N 谈话强奸收割系统。 | LI Hua LIANG Xinqiang CHEN Yingxu LIAN Yanfeng TIAN Guangming NI Wuzhong | 2008 | Journal of Environmental Sciences2008,20,2: | 27 |
| 5 | Ginkgo biloba extract improved cognitive and neurological functions of acute ischaemic stroke:a randomised controlled trial显示文摘Purpose To evaluate the efficacy and safety of Ginkgo biloba extract(GBE)in acute ischaemic stroke and its impact on the recurrence of vascular events.Methods We conducted a multicentre,prospective,randomised,open label,blinded,controlled clinical trial enrollingpatients with an onset of acute stroke within 7 days from five hospitals in China Jiangsu Province.Participants were assigned to the GBE group(450 mg GBE with 100 mg aspirin daily)or the control group(100 mg aspirin daily)for 6 months.The primary outcome was the decline in the Montreal Cognitive Assessment score at 6 months.Secondary outcomes were other neuropsychological tests of cognitive and neurological function,the the incidence of adverse events and vascular events.results 348 patients were enrolled:179 in the GBE group and 169 in the control group.With 18 patients lost to follow-up,the dropout rate was 5.17%.Admission data between two groups were similar,but in the GBE group there was a marked slow down in the decline in the Montreal Cognitive Assessment scores(−2.77±0.21 vs−1.99±0.23,P=0.0116(30 days);−3.34±0.24 vs−2.48±0.26,P=0.0165(90 days);−4.00±0.26 vs−2.71±0.26,P=0.0004(180 days))compared with controls.The National Institutes of Health Stroke Scale scores at 12 and 30 days,the modified Rankin Scale scores for independent rate at 30,90 and 180 days,and the Barthel Index scores at 30,90 and 180 days in the GBE group were significantly improved compared with controls.Improvements were also observedin GBE groups for Mini-Metal State Examination scores of 30,90 and 180 days,Webster's digit symbol test scores at 30 days and Executive Dysfunction Index scores at 30 and 180 days.No significant differences were seen in the incidence of adverse events or vascular events.conclusions We conclude that GBE in combination with aspirin treatment alleviated cognitive and neurological deficits after acute ischaemic stroke without increasing the incidence of vascular events. | Shanshan Li Xinjiang Zhang Qi Fang Junshan Zhou Meijuan Zhang Hui Wang Yan Chen Biyun Xu Yanfeng Wu Lai Qian Yun Xu | 2017 | Stroke & Vascular Neurology2017,2,4: | 25 |
| 6 | Advances on strategies for searching for next generation thermal barrier coating materials显示文摘Thermal barrier coating(TBC) materials play important roles in gas turbine engines to protect the Nibased super-alloys from the high temperature airflow damage. High melting point, ultra-low thermal conductivity, large thermal expansion coefficient, excellent damage tolerance and moderate mechanical properties are the main requirements of promising TBC materials. In order to improve the efficiency of jet and/or gas turbine engines, which is the key of improved thrust-to-weight ratios and the energysaving, significant efforts have been made on searching for enhanced TBC materials. Theoretically, density functional theory has been successfully used in scanning the structure and properties of materials, and at the same time predicting the mechanical and thermal properties of promising TBC materials for high and ultrahigh temperature applications, which are validated by subsequent experiments. Experimentally,doping and/or alloying are also widely applied to further decrease their thermal conductivities. Now, the strategy through combining theoretical calculations and experiments on searching for next generation thermal insulator materials is widely adopted. In this review, the common used techniques and the recent advantages on searching for promising TBC materials in both theory and experiments are summarized. | Bin Liu Yuchen Liu Changhua Zhu Huimin Xiang Hongfei Chen Luchao Sun Yanfeng Gao Yanchun Zhou | 2019 | Journal of Materials Science & Technology2019,35,5: | 24 |
| 7 | Graphene: a promising 2D material for electrochemical energy storage显示文摘Graphene, with unique two-dimensional form and numerous appealing properties, promises to remarkably increase the energy density and power density of electrochemical energy storage devices(EESDs),ranging from the popular lithium ion batteries and supercapacitors to next-generation high-energy batteries. Here, we review the recent advances of the state-of-the-art graphene-based materials for EESDs,including lithium ion batteries, supercapacitors, micro-supercapacitors, high-energy lithium-air and lithium-sulfur batteries, and discuss the importance of the pore, doping, assembly, hybridization and functionalization of different nano-architectures in improving electrochemical performance. The major roles of graphene are highlighted as(1) a superior active material,(2) ultrathin 2D flexible support,and(3) an inactive yet electrically conductive additive. Furthermore, we address the enormous potential of graphene for constructing new-concept emerging graphene-enabled EESDs with multiple functionalities of lightweight, ultra-flexibility, thinness, and novel cell configurations. Finally, future perspectives and challenges of graphene-based EESDs are briefly discussed. | Yanfeng Dong Zhong-Shuai Wu Wencai Ren Hui-Ming Cheng Xinhe Bao | 2017 | Science Bulletin2017,62,10: | 22 |
| 8 | Age-related rhesus macaque models of COVID-19显示文摘Background:Since December 2019,an outbreak of the Corona Virus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus(SARS-CoV-2)in Wuhan,China,has become a public health emergency of international concern.The high fatality of aged cases caused by SARS-CoV-2 was a need to explore the possible age-related phenomena with non-human primate models.Methods:Three 3-5 years old and two 15 years old rhesus macaques were intratracheally infected with SARS-CoV-2,and then analyzed by clinical signs,viral replication,chest X-ray,histopathological changes and immune response.Results:Viral replication of nasopharyngeal swabs,anal swabs and lung in old monkeys was more active than that in young monkeys for 14 days after SARS-CoV-2 challenge.Monkeys developed typical interstitial pneumonia characterized by thickened alveolar septum accompanied with inflammation and edema,notably,old monkeys exhibited diffuse severe interstitial pneumonia.Viral antigens were detected mainly in alveolar epithelial cells and macrophages.Conclusion:SARS-CoV-2 caused more severe interstitial pneumonia in old monkeys than that in young monkeys.Rhesus macaque models infected with SARS-CoV-2 provided insight into the pathogenic mechanism and facilitated the development of vaccines and therapeutics against SARS-CoV-2 infection. | Pin Yu Feifei Qi Yanfeng Xu Fengdi Li Peipei Liu Jiayi Liu Linlin Bao Wei Deng Hong Gao Zhiguang Xiang Chong Xiao Qi Lv Shuran Gong Jiangning Liu Zhiqi Song Yajin Qu Jing Xue Qiang Wei Mingya Liu Guanpeng Wang Shunyi Wang Haisheng Yu Xing Liu Baoying Huang Wenling Wang Li Zhao Huijuan Wang Fei Ye Weimin Zhou Wei Zhen Jun Han Guizhen Wu Qi Jin Jianwei Wang Wenjie Tan Chuan Qin | 2020 | Animal Models and Experimental Medicine2020,3,1: | 22 |
| 9 | Hybrid Material of Graphene and Poly(3,4-ethyldioxythiophene)with High Conductivity,Flexibility,and Transparency显示文摘A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily processed in both water and organic solvents.Conductivities of the order of 0.2 S/cm and light transmittance of greater than 80%in the 4001800 nm wavelength range were observed for fi lms with thickness of tens of nm.Practical applications in a variety of optoelectronic devices are thus expected for this transparent and flexible conducting graphene-based hybrid material。 | Yanfei Xu Yan Wang Jiajie Liang Yi Huang Yanfeng Ma Xiangjian Wan Yongsheng Chen | 2009 | Nano Research2009,2,4: | 23 |
| 10 | Whole-genome sequencing of 508 patients identifies key molecular features associated with poor prognosis in esophageal squamous cell carcinoma显示文摘Esophageal squamous cell carcinoma(ESCC)is a poor-prognosis cancer type with limited understanding of its molecular etiology.Using 508 ESCC genomes,we identified five novel significantly mutated genes and uncovered mutational signature clusters associated with metastasis and patients’outcomes.Several functional assays implicated that NFE2L2 may act as a tumor suppressor in ESCC and that mutations in NFE2L2 probably impaired its tumor-suppressive function,or even conferred oncogenic activities.Additionally,we found that the NFE2L2 mutations were significantly associated with worse prognosis of ESCC.We also identified potential noncoding driver mutations including hotspot mutations in the promoter region of SLC35E2 that were correlated with worse survival.Approximately 5.9%and 15.2%of patients had high tumor mutation burden or actionable mutations,respectively,and may benefit from immunotherapy or targeted therapies.We found clinically relevant coding and noncoding genomic alterations and revealed three major subtypes that robustly predicted patients’outcomes.Collectively,we report the largest dataset of genomic profiling of ESCC useful for developing ESCC-specific biomarkers for diagnosis and treatment. | Yongping Cui Hongyan Chen Ruibin Xi Heyang Cui Yahui Zhao Enwei Xu Ting Yan Xiaomei Lu Furong Huang Pengzhou Kong Yang Li Xiaolin Zhu Jiawei Wang Wenjie Zhu Jie Wang Yanchun Ma Yong Zhou Shiping Guo Ling Zhang Yiqian Liu Bin Wang Yanfeng Xi Ruifang Sun Xiao Yu Yuanfang Zhai Fang Wang Jian Yang Bin Yang Caixia Cheng Jing Liu Bin Song Hongyi Li Yi Wang Yingchun Zhang Xiaolong Cheng Qimin Zhan Yanhong Li Zhihua Liu-Show | 2020 | Cell Research2020,30,10: | 19 |
| 11 | Mesozoic-Cenozoic Multi-Stage Intraplate Deformation Events in the Langshan Region and their Tectonic Implications显示文摘In the Langshan region, northwestern China, marked multi-stage intraplate deformation events have occurred since the Mesozoic, including(1) northeast-striking ductile left-lateral strike slip during the Middle-Late Triassic, which is closely related to the collision between the North China and the Yangtze plates;(2) top-to-the-southeast thrust with northwest-southeast trending maximum compression during the Late Jurassic;(3) nearly eastward detachment during the Early Cretaceous;(4) top-to-the-northwest thrust with northwest-southeast trending maximum compression during the Late Cretaceous and Early Cenozoic;(5) northeast-striking brittle left-lateral strike slip with nearly north-south trending maximum compression; and(6) northwest-southeast extension during the Middle-Late Cenozoic. All these deformation events belong to the intraplate deformation across the entire Central Asian region and respond to the tectonic events along the plate boundaries or deep tectonics. The structures developed in early events in the crust were the most important factors controlling the later deformation styles, and few new structures have later developed. Based on previous research and our results, the paleostress inversion in the Langshan region shows that the Mesozoic intraplate deformations in the study region mainly resulted from the tectonic events from the Paleo-Pacific region and have no or a weak relation to the Tethys region. During the Late Jurassic, the maximum compression from the Mongolia-Okhotsk region cannot be excluded. The Langshan region is the bridge between southern Mongolia and the western Ordos tectonic belt and is thus important to understand the nature and relationship between both regions. | ZHANG Jin LI Jinyi LI Yanfeng QI Wenhua ZHANG Yiping | 2014 | Acta Geologica Sinica(English Edition)2014,88,1: | 18 |
| 12 | Hidden policy ciphertext-policy attribute-based encryption with keyword search against keyword guessing attack显示文摘Attribute-based encryption with keyword search(ABKS) enables data owners to grant their search capabilities to other users by enforcing an access control policy over the outsourced encrypted data. However,existing ABKS schemes cannot guarantee the privacy of the access structures, which may contain some sensitive private information. Furthermore, resulting from the exposure of the access structures, ABKS schemes are susceptible to an off-line keyword guessing attack if the keyword space has a polynomial size. To solve these problems, we propose a novel primitive named hidden policy ciphertext-policy attribute-based encryption with keyword search(HP-CPABKS). With our primitive, the data user is unable to search on encrypted data and learn any information about the access structure if his/her attribute credentials cannot satisfy the access control policy specified by the data owner. We present a rigorous selective security analysis of the proposed HP-CPABKS scheme, which simultaneously keeps the indistinguishability of the keywords and the access structures. Finally,the performance evaluation verifies that our proposed scheme is efficient and practical. | Shuo QIU Jiqiang LIU Yanfeng SHI Rui ZHANG | 2017 | Science China(Information Sciences)2017,60,5: | 18 |
| 13 | Effect of thermomechanical treatment on microstructure and properties of Cu-Cr-Zr-Ag alloy显示文摘The effects of thermomechanical treatment on the properties and microstructure of Cu-Cr-Zr alloy and Cu-Cr-Zr-Ag alloy were investigated. Ag addition improves the mechanical properties of the alloy through solid solution strengthening and brings a little effect on the electrical conductivity of the alloy. A new Cu-Cr-Zr-Ag alloy was developed, which has an excellent combination of the tensile strength, elongation, and electrical conductivity reaching 476.09 MPa, 15.43% and 88.68% IACS respectively when subjected to the optimum thermomechanical treatment, i.e., solution-treating at 920°C for 1 h, cold drawing to 96% deformation, followed by aging at 400°C for 3 h. TEM analysis re-vealed two kinds of finely dispersed precipitates of Cr and Cu4Zr. It is very important to use the mechanisms of solid solution strengthening, work hardening effect as well as precipitate pinning effect of dislocations to improve tensile strength of the alloy without adversely affecting its electrical conductivity. | XIE Haofeng MI Xujun HUANG Guojie GAO Baodong YIN Xiangqian LI Yanfeng | 2011 | Rare Metals2011,30,6: | 17 |
| 14 | Toxicities and risk assessment of heavy metals in sediments of Taihu Lake, China, based on sediment quality guidelines显示文摘The occurrence, toxicities, and ecological risks of five heavy metals(Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the toxicities induced by organic contaminants and ammonia in the sediments were screened out with activated carbon and zeolite. The toxicities of heavy metals in sediments were tested with benthic invertebrates(tubificid and chironomid).The correlations between toxicity of sediment and the sediment quality guidelines(SQGs)derived previously were evaluated. There were significant correlations(p < 0.0001) between the observed toxicities and the total risk quotients of the heavy metals based on SQGs,indicating that threshold effect level(TEL) and probable effect level(PEL) were reliable to predict the toxicities of heavy metals in the sediments of Taihu Lake. By contrast, the method based on acid volatile sulfides(AVS) and simultaneously extracted metals(SEM),such as ∑SEM/AVS and ∑SEM-AVS, did not show correlations with the toxicities. Moreover,the predictive ability of SQGs was confirmed by a total predicting accuracy of 77%. Ecological risk assessment based on TELs and PELs showed that the contaminations of Pb, Cu, Cd and Zn in the sediments of Taihu Lake were at relatively low or medium levels. The risks caused by heavy metals in the sediments of northern bay of the lake, which received more wastewater discharge from upper stream, were higher than other area of the lake. | Yanfeng Zhang Yuwei Han Jinxi Yang Lingyan Zhu Wenjue Zhong | 2017 | Journal of Environmental Sciences2017,29,12: | 16 |
| 15 | Development of land use transitions research in China显示文摘With the introduction of the concept of land use transition into China,related researches have been carried out extensively in the past two decades,which enrich the knowledge of land system science.This paper describes the development of research on land use transitions in China from the perspectives of conceptual connotations,theoretical model,research methods,and research progress and prospects.With the in-depth investigation of land use transitions,the concept and connotations of land use morphology are developed and encapsulated as two kinds,i.e.,dominant morphology and recessive morphology.The dominant morphology refers to the land use structure of a certain region over a certain period of time,with features such as the quantity and spatial pattern of land use types.While the recessive morphology includes the land use features in the aspects of quality,property rights,management mode,input,output and function.Accordingly,the concept of land use transition is further developed,and the theoretical model of regional land use transitions is established.Thereafter,three innovative integrated approaches to study land use transitions are put forward,i.e.,multidisciplinary research framework for recessive land use transition,transect and horizontal comparison.To date,there have been 62 Ph.D.and 166 M.S.dissertations on the topic of'land use transition'in China.During 2002–2019,the National Natural Science Foundation of China has funded 48 research programs on the theme of'land use transition'.As such,the Chinese scholars have adapted the concept derived from western literature to the situations and experiences in China. | LONG Hualou QU Yi TU Shuangshuang ZHANG Yingnan JIANG Yanfeng | 2020 | Journal of Geographical Sciences2020,30,7: | 15 |
| 16 | Low-dose decitabine enhances the effect of PD-1 blockade in colorectal cancer with microsatellite stability by re-modulating the tumor microenvironment显示文摘PD-1 blockade has demonstrated impressive clinical outcomes in colorectal cancers that have high microsatellite instability.However,the therapeutic efficacy for patients with tumors with low microsatellite instability or stable microsatellites needs further improvement.Here,we have demonstrated that low-dose decitabine could increase the expression of immune-related genes such as major histocompatibility complex genes and cytokine-related genes as well as the number of lymphocytes at the tumor site in CT26 colorectal cancer-bearing mice.A more significant inhibition of tumor growth and a prolongation of survival were observed in the CT26 mouse model after treatment with a combination of PD-1 blockade and decitabine than in mice treated with decitabine or PD-1 blockade alone.The anti-tumor effect of the PD-1 blockade was enhanced by low-dose decitabine.The results of RNA sequencing and whole-genome bisulfite sequencing of decitabine-treated CT26 cells and tumor samples with microsatellite stability from the patient tumor-derived xenograft model have shown that many immune-related genes,including antigen-processing and antigen-presenting genes,were upregulated,whereas the promoter demethylation was downregulated after decitabine exposure.Therefore,decitabine-based tumor microenvironment re-modulation could improve the effect of the PD-1 blockade.The application of decitabine in PD-1 blockade-based immunotherapy may elicit more potent immune responses,which can provide clinical benefits to the colorectal cancer patients with low microsatellite instability or stable microsatellites. | Ganjun Yu Yanfeng Wu Wenying Wang Jia Xu Xiaoping Lv Xuetao Cao Tao Wan | 2019 | Cellular & Molecular Immunology2019,16,4: | 14 |
| 17 | Complex conductivity and permittivity of single wall carbon nanotubes/polymer composite at microwave frequencies:A theoretical estimation显示文摘Based on an equivalent resistance-capacitance network, the complex conductivity and the relative complex permittivity of single wall carbon nanotubes (SWNTs)/polymer composite are theoretically investigated in the frequency range of 0.30-18 GHz using the logarithmic rule. Both the real and imaginary parts of the permittivities of SWNTs and polymer are considered in detail. The calculated complex permittivity spectra of SWNTs/poly(ethyl methacrylate) composite films are in good agreement with the available experimental data. The influences of SWNTs concentration on both the complex conductivity and the dielectric loss tangent of the composite are presented in the microwave frequency range. A linear relationship between microwave conductivity and frequency is found. | PENG ZhiHua PENG JingCui PENG YanFeng WANG JieYang | 2008 | Chinese Science Bulletin2008,53,22: | 13 |
| 18 | Effects of culm carbohydrate partitioning on basal stem strength in a high-yielding rice population显示文摘Rice culm carbohydrate transport can simultaneously affect grain filling and stem lodging resistance by regulating non-structural carbohydrate(NSC) and structural carbohydrate(SC) contents. However, the relationship between carbohydrate transposition and culm strength is not well documented. Accordingly, a high-yielding hybrid rice cultivar(Y Liangyou 2) was tested under different N fertilization regimes at two locations, Taoyuan(a special high-yield eco-site), Yunnan province and Danyang(a representative eco-site of the middle and lower Yangtze), Jiangsu province, China. Significantly higher grain yield and basal stem strength were found at Taoyuan than Danyang under all N rates throughout the two-year experiment. At heading stage, soluble sugars, starch, cellulose and lignin contents of the basal culm at Taoyuan were significantly 132.0%, 73.7%, 1.2%, and 62.7% higher than those at Danyang, respectively. At 20 days after heading, soluble sugars and starch content at Taoyuan decreased significantly compared to Danyang, but lignin content remained higher. Culm carbohydrate transport to kernels at Taoyuan was significantly greater than that at Danyang, and the proportion of soluble sugars and starch was correspondingly 62.9%lower. However, the proportion of lignin and cellulose was 22.7% higher at Taoyuan than that at Danyang. Soluble sugars and starch partitioning were significantly reduced under an increased nitrogen application rate, but SC partitioning was little affected. There were significant positive correlations between basal culm bending stress and dry weight and cellulose and lignin proportions at both locations under all N rates, suggesting that the higher SC proportion at 20 days after heading was primarily responsible for culm strength.These results suggest that high-yielding rice populations with greater culm strength require both moderate NSC transport and greater SC accumulation. | Jun Zhang Ganghua Li Qingyu Huang Zhenghui Liu Chengqiang Ding She Tang Lin Chen Shaohua Wang Yanfeng Ding Weijian Zhang | 2017 | The Crop Journal2017,5,6: | 13 |
| 19 | Glial cell-derived neurotrophic factor mRNA expression in a rat model of spinal cord injury following bone marrow stromal cell transplantation显示文摘BACKGROUND: Several animal experiments utilizing bone marrow stromal cell (BMSC) transplantation for the treatment of spinal cord injury have proposed a hypothesis that BMSC transplantation effects are associated with increased glial cell-derived neurotrophic factor (GDNF) expression. OBJECTIVE: To confirm the effects of BMSC transplantation on GDNF mRNA expression in rats with spinal cord injury by reverse transcription-polymerase chain reaction (RT-PCR). DESIGN, TIME AND SETTING: The present molecular, cell biology experiment was performed at the Key Laboratory of Children's Congenital Malformation, Ministry of Health of China & Department of Developmental Biology, Basic Medical College, China Medical University between March 2006 and May 2007. MATERIALS: Sixty healthy Wistar rats aged 2-4-months and of either gender were included in this study. Spinal cord injury was induced in all rats by hemisection of T9 on the left side. RT-PCR kits were purchased from TaKaRa Company, China. Type 9600 RCR amplifier was provided by PerkinElmer Company, USA. METHODS: Three rats were selected for BMSC culture and subsequent transplantation (after three passages). Of the remaining 57 rats, nine were selected for sham-operation (sham-operated group), where only the T9 spinal cord was exposed without hemisection. A total of 48 rats were randomly and evenly divided into BMSC transplantation and model groups. In the BMSC transplantation group, following spinal cord injury induction, each rat was administered a BMSC suspension through two injection sites selected on the gray and white matter boundary caudally and cephalically, seperately and near to injury site in the spinal cord. The model group received an equal volume of PBS through the identical injection sites. MAIN OUTCOME MEASURES: At 24 and 72 hours, as well as at 7 days, following spinal cord injury, the spinal cord at the T 9 segment was removed. Eight rats were allocated to each time point in the BMSC transplantation and model groups, with three rats allocated to the sham-operated group. GDNF mRNA expression was semiquantitatively analyzed by RT-PCR. RESULTS: The sham-operated group exhibited extremely low GDNF mRNA expression. GDNF mRNA expression significantly increased at 24 hours after spinal cord injury, reached a peak level at 72 hours, and slowly decreased thereafter. However, it remained higher than normal levels at 7 days (P < 0.05). At all time points following spinal cord injury, GDNF mRNA expression was significantly greater in the BMSC transplantation group than in the model group (P < 0.05). CONCLUSION: Transplantation of BMSCs into the injured spinal cord up-regulated GDNF mRNA expression, thereby promoting repair of the injured spinal cord. | Lei Li Gang Lu Yanfeng Wang Hong Gao XinXu Lunhao Bai Lunhao Bai Huan Wang | 2008 | Neural Regeneration Research2008,3,10: | 13 |
| 20 | Direct low-temperature synthesis of graphene on various glasses by plasma-enhanced chemical vapor deposition for versatile, cost-effective electrodes显示文摘在低温度的各种各样的玻璃底层上的 graphene 的没有催化剂、可伸缩的合成具有到象便宜透明电子学和最先进的显示器那样的众多的应用程序的首要的意义。然而,在这个有希望的研究领域以内的系统的学习远这样仍然保持少见。此处,我们用一个低温度的提高血浆的化学蒸汽免职方法在各种各样的眼镜上报导 graphene 的直接生长。如此的一条灵巧、可伸缩的途径在 400600 的一个生长温度范围在各种各样的玻璃底层上保证一致、没有转移的 graphene | Jingyu Sun Yubin Chen Xin Cai Bangjun Ma Zhaolong Chen Manish Kr. Priydarshi Ke Chen Teng Gao Xiuju Song Qingqing Ji Xuefeng Guo Dechun Zou Yanfeng Zhang Zhongfan Liu | 2015 | Nano Research2015,8,11: | 12 |