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66篇 您的检索式:作者名="DING LiPing"
    题名 作者 年代 出处 被引量
1Guidelines for evaluation and management of cerebral collateral circulation in ischaemic stroke 2017显示文摘Collateral circulation plays a vital role in sustaining blood flow to the ischaemic areas in acute,subacute or chronic phases after an ischaemic stroke or transient ischaemic attack.Good collateral circulation has shown protective effects towards a favourable functional outcome and a lower risk of recurrence in stroke attributed to different aetiologies or undergoing medical or endovascular treatment.Over the past decade,the importance of collateral circulation has attracted more attention and is becoming a hot spot for research.However,the diversity in imaging methods and criteria to evaluate collateral circulation has hindered comparisons of findings from different cohorts and further studies in exploring the clinical relevance of collateral circulation and possible methods to enhance collateral flow.The statement is aimed to update currently available evidence and provide evidence-based recommendations regarding grading methods for collateral circulation,its significance in patients with stroke and methods under investigation to improve collateral flow.Liping Liu Jing Ding Xinyi Leng Yuehua Pu Li-An Huang Anding Xu Ka Sing Lawrence Wong Xin Wang Yongjun Wang 2018Stroke & Vascular Neurology2018,3,3:37
2Multispherical interactions and their effects on the Tibetan Plateau's earth system: a review of the recent researches显示文摘The Tibetan Plateau(TP) is a regional Earth system showing very strong interactions among its lithosphere, hydrosphere, cryosphere, biosphere, atmosphere, and anthrosphere. hese interactions manifest TP's impact on surrounding regions and relect TP's response to the global change. Quantifying the multispherical interactions is critically important to understand the TP environment. Our recent years researches including the ongoing program entitled ‘Tibetan Multi-Spheres Interactions and heir Resource-Environment Signiicance(TIMI)', the completed program entitled. ‘Paleo-Altitudes of Tibetan Plateau and Environment(PATE)', as well as the other relating projects have focused on multidisciplinary research approaches and emphasized on three major pathways: Eurasia-Indian plates collision on deep-Earth dynamics, uplit impact on Earth's mantle–crust dynamics, and contemporary interface on land surface and atmospheric dynamics. Our researches have taken in situ measurement as priority and developed several platforms of data acquisition and analysis, including the platforms of water-phase transformations, and ecosystem observations. Our ield investigations have been conducted to obtain data about stratum, paleontology, paleoenvironment, genetic diferentiation of animals and plants. We have developed conceptual and mathematical models for crust uplit formation, paleoclimate, glacial melt,water–air interface lux, vegetation climate, and soil erosion. We have also assessed the anthropogenic impacts on environment. Our researches have achieved new and reliable redating of the mantle–crust interaction and initial formation of the TP, found the interaction between tectonics and uplit of the TP and resultant paleoaltitude acting as a spreading source; discovered the interaction between the westerlies and Indian monsoon acting as a control chain that dominates the TP's contemporary environment. he scientiic results can play fundamental roles in supporting the TP's resource exploration and societal sustainable development.Tandong Yao Fuyuan Wu Lin Ding Jimin Sun Liping Zhu Shilong Piao Tao Deng Xijun Ni Hongbo Zheng Hua Ouyang 2015National Science Review2015,2,4:35
3Effect of Saccharomyces cerevisiae on alfalfa nutrient degradation characteristics and rumen microbial populations of steers fed diets with different concentrate-to-forage ratios显示文摘Live yeast(Saccharomyces cerevisiae) constitutes an effective additive for animal production;its probiotic effect may be related to the concentrate-to-forage ratio(CTFR).The objective of this study was to assess the effects of S.cerevisiae(SC) on fiber degradation and rumen microbial populations in steers fed diets with different levels of dietary concentrate.Ten Simmental × Local crossbred steers(450 ± 50 kg BW) were assigned to a control group or an SC group.Both groups were fed the same basal diet but the SC group received SC supplementation(8 × 10~9 cfu/h/d through the ruminal fistula)following a two-period crossover design.Each period consisted of four phases,each of which lasted 17 d:10 d for dietary adaptation,6 d for degradation study,and 1 d for rumen sample collection.From the 1^(st) to the 4^(th) phase,steers were fed in a stepwise fashion with increasing CTFRs,i.e.,30:70,50:50,70:30,and 90:10.The kinetics of dry matter and fiber degradation of alfalfa pellets were evaluated;the rumen microbial populations were detected using real-time PCR.The results revealed no significant(P> 0.05) interactions between dietary CTFR and SC for most parameters.Dietary CTFR had a significant effect(P< 0.01) on degradation characteristics of alfalfa pellets and the copies of rumen microorganism;the increasing concentrate level resulted in linear,quadratic or cubic variation trend for these parameters.SC supplementation significantly(P< 0.05) affected dry matter(DM) and neutral detergent fiber(NDF)degradation rates(c_(DM),c_(NDF)) and NDF effective degradability(ED_(NDF)).Compared with the control group,there was an increasing trend of rumen fungi and protozoa in SC group(P < 0.1);copies of total bacteria in SC group were significantly higher(P< 0.05).Additionally,percentage of Ruminobacter amylophilus was significantly lower(P< 0.05)but percentage of Selenomonas ruminantium was significantly higher(P< 0.05) in the SC group.In a word,dietary CTFR had a significant effect on degradation characteristics of forage and rumen microbial population.S.cerevisiae had positive effects on DM and NDF degradation rate or effective degradability of forage;S.cerevisiae increased rumen total bacteria,fungi,protozoa,and lactate-utilizing bacteria but reduced starch-degrading and lactate-producing bacteria.Gengzhi Ding Ying Chang Liping Zhao Zhenming Zhou Liping Ren Qingxiang Meng 2014Journal of Animal Science and Biotechnology2014,5,4:15
4Prostate cancer in Asia:A collaborative report显示文摘The incidence of prostate cancer(PCa)within Asian population used to be much lower than in the Western population;however,in recent years the incidence and mortality rate of PCa in some Asian countries have grown rapidly.This collaborative report summarized the latest epidemiology information,risk factors,and racial differences in PCa diagnosis,current status and new trends in surgery management and novel agents for castration-resistant prostate cancer.We believe such information would be helpful in clinical decision making for urologists and oncologists,health-care ministries and medical researchers.Rui Chen Shancheng Ren Ming Kwong Yiu Ng Chi Fai Wai Sam Cheng Lap Hong Ian Seiji Naito Tadashi Matsuda Elijah Kehinde Ali Kural Jason Yichun Chiu Rainy Umbas Qiang Wei Xiaolei Shi Liqun Zhou Jian Huang Yiran Huang Liping Xie Lulin Ma Changjun Yin Danfeng Xu Kexin Xu Zhangqun Ye Chunxiao Liu Dingwei Ye Xin Gao Qiang Fu Jianquan Hou Jianlin Yuan Dalin He Tiejun Pan Qiang Ding Fengshuo Jin Benkang Shi Gongxian Wang Xiuheng Liu Dongwen Wang Zhoujun Shen Xiangbo Kong Wanhai Xu Yaoliang Deng Haibo Xia Alexa NCohen Xu Gao Chuanliang Xu Yinghao Sun 2014Asian Journal of Urology2014,1,1:13
5Endovascular treatment with or without intravenous alteplase for acute ischaemic stroke due to basilar artery occlusion显示文摘Background and purpose It remains controversial if endovascular treatment(EVT)can improve the outcome of patients with acute basilar artery occlusion(BAO).This study aims to compare the functional outcomes between EVT with and without intravenous thrombolysis(IVT)first in patients who had acute ischaemic stroke(AIS)due to BAO.Methods Patients who had AIS with BAO who underwent EVT within 24 hours of onset were enrolled in this multicentre cohort study,and the efficacy and safety were compared between IVT+EVT and direct EVT.The primary outcome was 90-day functional independence.All outcomes were assessed with adjusted OR(aOR)from the multivariable logistic regression.In addition,a meta-analysis was performed on all recently published pivotal studies on functional independence after EVT in patients with BAO.Results Of 310 enrolled patients with BAO,241(78%)were treated with direct EVT and 69(22%)with IVT+EVT.Direct EVT was associated with a worse functional outcome(aOR,0.46(95%CI 0.24 to 0.85),p=0.01).IVT+EVT was associated with a lower percentage of patients who needed≥3 passes of stent retriever(10.14%vs 20.75%).The meta-analysis regression revealed a potential positive correlation between bridging with IVT first and functional independence(r=0.14(95%CI 0.05 to 0.24),p<0.01).Conclusions This study showed that compared with direct EVT,EVT with IVT first was associated with better functional outcomes in patients with BAO treated within 24 hours of onset.The meta-analysis demonstrated similar favourable efficacy of IVT first followed by EVT in patients with BAO.Ximing Nie David Wang Yuehua Pu Yufei Wei Qixuan Lu Hongyi Yan Xin Liu Lina Zheng Jingyi Liu Xinxuan Yang Yarong Ding Dacheng Liu Wanying Duan Zhe Zhang Zhonghua Yang Miao Wen Weibin Gu Xinyi Hou Xinyi Leng Yuesong Pan Zhongrong Miao Liping Liu 2022Stroke & Vascular Neurology2022,7,3:10
6Estimation of Endocarpon pusillum Hedwig carbon budget in the Tengger Desert based on its photosynthetic rate显示文摘This study investigated the photosynthetic rate of the lichen Endocarpon pusillum at the Chinese Academy of Sciences Shapotou Desert Research Station and estimated its annual contribution to the carbon budget in the ecosystem. The software SigmaPlot 10.0 with 'Macro-Area below curves' was used to calculate the carbon fixation capacity of the lichen. The total carbon budget (ΣC) of the lichen was obtained by subtracting the respiratory carbon loss (ΣDR) from the photosynthetic carbon gain (ΣNP). Because water from precipitation plays an important role in photosynthesis in this ecosystem, the annual carbon budget of E. pusillum at the station was estimated based on the three-year average precipitation data from 2009 to 2011. Our results indicate that the lichen fixes 14.6 g Cm-2 annually. The results suggest that artificial inoculation of the crust lichen in the Tengger Desert could not only help reduce the sand and dust storms but also offer a significant carbon sink, fixing a total of 438000 t of carbon over the 30000 km2 of the Tengger Desert. The carbon sink could potentially help mitigate the atmospheric greenhouse effect. Our study suggests that the carpet-like lichen E. pusillum is an excellent candidate for 'Bio-carpet Engineering' of arid and semi-arid regions.DING LiPing ZHOU QiMing WEI JiangChun 2013Science China(Life Sciences)2013,56,9:9
7Regional Δ~14C patterns and fossil fuel derived CO_2 distribution in the Beijing area using annual plants显示文摘The level of atmosphericΔ14C and the fossil fuel derived CO 2 concentration in the Beijing area from May to September,2009, were systematically analyzed based on radiocarbon(14C)measurements of annual plants by accelerator mass spectrometry(AMS). The results show that the maximumΔ14C in Beijing was 29.6‰±2.2‰,and the minimum was–28.2‰±2.5‰,with a trend of decreasingΔ14C from the outer suburbs to inner suburbs to the urban center.This trend correlates well with increases in fossil fuel derived CO2 caused by human activities such as population density,industrial emissions and traffic,with lower values of atmosphericΔ14C associated with more intensive human activities.The fossil fuel derived CO 2 concentrations from May to September, 2009,ranged from 3.9±1.0 ppm to 25.4±1.0 ppm.It was calculated that each additional 1 ppm of CO2 from fossil fuels depleted the atmosphericΔ14C by approximately 2.70‰.This study suggests that 14C measurements of annual plants by AMS provide an effective method to rapidly trace fossil fuel derived CO2.XI XianTing DING XingFang FU DongPo ZHOU LiPing LIU KeXin 2011Chinese Science Bulletin2011,56,16:7
8Toxic effects of 1-methyl-3-octylimidazolium bromide on the wheat seedlings显示文摘The toxic effects of 1-methyl-3-octylimidazolium bromide ([C8 mim]Br) on wheat seedlings were evaluated.Wheat seedlings were cultivated in aqueous solution with [C8 mim]Br at different concentrations (0,1,2,4,6,8 mg/L).The contents of photosynthetic pigment and proline,peroxidation of membrane lipid,and activities of antioxidation enzymes (superoxide dismutase,catalase,peroxidase and ascorbate peroxidase) in leaves were measured on day 7 after treatment with [C8 mim]Br.The results showed that [C8 mim]Br significantly decreased the contents of photosynthetic pigments,activities of antioxidant enzymes in the wheat leaves and in dry weight of seedlings,while increased the proline content and membrane lipid peroxidation.The results suggested that [C8 mim]Br can inhibit photosynthesis and lead to oxidative stress to wheat seedlings.Ping Liu Yifeng Ding Haiying Liu Liping Sun Xiaoyu Li Jianji Wang 2010Journal of Environmental Sciences2010,22,12:6
9The Glacier Area Changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate Change显示文摘Glacier area changes in the Qangtang Plateau are analyzed during 1970-2000 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid method.The results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2000 in the whole Qangtang Plateau.However,the glaciers seemed still more stable in the study area than in most areas of western China.We estimate that glacier retreat was likely due to air temperature warming during 1970-2000 in the Qangtang Plateau.Furthermore,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.WANG Liping XIE Zichu WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui 2011Journal of Mountain Science2011,8,6:5
10Exposing Cu-rich {110} active facets in PtCu nanostars for boosting electrochemical performance toward multiple liquid fuels electrooxidation显示文摘In catalysis,tuning the structural composition of the metal alloy is known as an efficient way to optimize the catalytic activity.This work presents the synthesis of compositional segregated six-armed PtCu nanostars via a facile solvothermal method and their distinct composition-structure-dependent performances in electrooxidation processes.The alloy is shown to have a unique six arms with a Cu-rich dodecahedral core,mainly composed of {110} facets and exhibit superior catalytic activity toward alcohols electrooxidation compared to the hollow counterpart where Cu was selectively etched.Density functional theory (DFT) calculations suggest that the formation of hydroxyl intermediate (OH^*) is crucial to detoxify CO poisoning during the electrooxidation processes.The addition of Cu is found to effectively adjust the d band location of the alloy catalyst and thus enhance the formation of ^*OH intermediate from water splitting,which decreases the coverage of ^*CO intermediate.Our work demonstrates that the unique compositional anisotropy in alloy catalyst may boost their applications in electrocatalysis and provides a methodology for the design of this type catalyst.Liping Huang Wei Zhang Peng Li Yongbo Song Hongting Sheng Yuanxin Du Yang-Gang Wang Yuen Wu Xun Hong Yanhuai Ding Xiaoyou Yuan Manzhou Zhu 2019Nano Research2019,12,5:4
11Loss of Wip1 aggravates brain injury after ischaemia/reperfusion by overactivating microglia显示文摘Background and purpose The inflammatory response mediated by microglia/macrophages is closely related to cerebral ischaemia/reperfusion injury.Wild-type p53-induced protein phosphatase 1(Wip1),a serine/threonine phosphatase,is expressed in various tissues.A growing number of reports have suggested that Wip1 is a negative regulator of inflammation in peripheral tissue;however,its role in the central nervous system(CNS)remains unclear.This study aimed to clarify whether Wip1 can inhibit CNS inflammation by regulating microglia/macrophage functions after ischaemic injury.Methods A model of middle cerebral artery occlusion and reperfusion was established in mice.CNS inflammation was simulated by lipopolysaccharide treatment of primary microglia.Laser speckle imaging was used to monitor regional cerebral blood flow.Behavioural outcomes were assessed with a TreadScan gait analysis system.TTC staining was used to evaluate the infarct volume,and western blotting and immunofluorescence staining were applied to detect the phenotypical transformation of microglia.ELISA was performed to detect the levels of inflammatory factors.Results Wip1 expression was increased after ischaemia/reperfusion.Wip1-knockout(KO)mice displayed more severe brain injury than wild-type mice,as indicated by aggravated motor dysfunction,greater brain infarct volumes and higher expression of inflammatory cytokines(interleukin-6 and tumour necrosis factor alpha)in the brain.We also found that Wip1 depletion increased microglial/macrophage activation in both in vitro and in vivo models,which all showed activation of microglia/macrophages.Lentivirus-Ppm1d reversed the injury induced by Wip1-KO.Conclusions Our results suggest that Wip1 may inhibit neuroinflammation by inhibiting microglial/macrophage activation after brain ischaemia/reperfusion injury.Feng Yan Xiang Cheng Ming Zhao Shenghui Gong Ying Han Liping Ding Di Wu Yumin Luo Wei Zuo Lingling Zhu Ming Fan Xunming Ji 2021Stroke & Vascular Neurology2021,6,3:4
12Hyaluronidase-triggered anticancer drug and siRNA delivery from cascaded targeting nanoparticles for drug- resistant breast cancer therapy显示文摘药抵抗在结缔组织生长的治疗使标准化疗变为无效因素(CTGF )-overexpressing 乳癌。由共同嵌入胸肿瘤渗透房间的肽( PEGA-pVEC )和玻尿的酸(哈)作为指向媒介,新奇串联指向的 nanoparticles ( HACT NP )在格格声 mesoporous 硅石上被创造(为与 anticancer 药一起的 siRNAs 的针尖交货的 rmSiO 2)支架,瞄准在 vivo 克服 CTGF-overexpressing 乳癌的药抵抗。指向的 nanoparticles 有选择地在 PEGA-pVEC 肽的指导下面在 vasculature 积累了,在另一个指向的代理人的帮助下由调停受体的 endocytosis 串联了,哈,介绍一在比单个指向指向能力的 vivo 肿瘤更大 ligand 向量。另外, HA 壳在货物运输过程期间阻止了治疗学的药的漏直到玻尿酸酵素(HAase ) 在 lysosomes 进入之上触发了降级,保证在目标房间内的一个可控制的药版本。当保护的壳瓦解时,释放 siRNA 负责了到基因与药抵抗联系了的沉默, CTGF,因此便于导致 doxorubicin 的 apoptosis。串联指向的媒介(PEGA-pVEC 并且哈) 在 vivo 推进指导精确的治疗,当进一个化疗药交货系统的 siRNAs 的封装为药抵抗癌症的治疗提供有效策略时。Jie Ding Tingxizi Liang Ying Zhou Zhiwei He Qianhao Min Liping Jiang Junjie Zhu 2017Nano Research2017,10,2:2
13Application of fluorescence in situ hybridization in the detection of bladder transitional-cell carcinoma: A multi-center clinical study based on Chinese population显示文摘Objective:To evaluate the diagnostic value of fluorescence in situ hybridization(FISH)in bladder cancer.Methods:We enrolled healthy volunteers and patients who were clinically suspected to have bladder cancer and conducted FISH tests and cytology examinations from August 2007 to December 2008.Receiver operating characteristic(ROC)curve analysis was performed and the area under curve(AUC)values were calculated for both the FISH and urine cytology tests.Results:A cohort of 988 healthy volunteers was enrolled to establish a reference range for the normal population.A total of 4807 patients with hematuria were prospectively,randomly enrolled for the simultaneous analysis of urine cytology,FISH testing,and a final diagnosis as determined by the pathologic findings of a biopsy or a surgically-excised specimen.Overall,the sensitivity of FISH in detecting transitional-cell carcinoma was 82.7%,while that of cytology was 33.4%(p<0.001).The sensitivity values of FISH for non-muscle invasive and muscle invasive bladder transitional-cell carcinoma were 81.7%and 89.6%,respectively(p=0.004).The sensitivity values of FISH for low and high grade bladder cancer were 82.6%and 90.1%,respectively(p=0.002).Conclusion:FISH is significantly more sensitive than voided urine cytology for detecting bladder cancer in patients evaluated for gross hematuria at all cancer grades and stages.Higher sensitivity using FISH was obtained in high grade and muscle invasive tumors.Liqun Zhou Kaiwei Yang Xuesong Li Yi Ding Dawei Mu Hanzhong Li Yong Yan Jinyi Li Dongwen Wang Wei Li Yulong Cong Jiangping Gao Kewei Ma Yajun Xiao Sheng Zhang Hongyi Jiang Weilie Hu Qiang Wei Xunbo Jin Zhichen Guan Qingyong Liu Danfeng Xu Xin Gao Yongguang Jiang Weimin Gan Guang Sun Qing Wang Yanhui Liu Jianquan Hou Liping Xie Xishuang Song Fengshuo Jin Jiafu Feng Ming Cai Zhaozhao Liang Jie Zhang Dingwei Ye Lin Qi Lulin Ma Jianzhong Shou Yuping Dai Jianyong Shao Ye Tian Shizhe Hong Tao Xu Chuize Kong Zefeng Kang Yuexin Liu Xun Qu Benkang Shi Shaobin Zheng Yi Lin Shujie Xia Dong Wei Jianbo Wu Weiling Fu Zhiping Wang Jianbo Liang 2019Asian Journal of Urology2019,6,1:2
14Serum trimethylamine-N-oxide and gut microbiome alterations are associated with cholesterol deposition in the liver of laying hens fed with rapeseed meal显示文摘Sinapine derived from cruciferous plants could be converted into trimethylamine by intestinal microbiota.Its metabolite,trimethylamine N-oxide(TMAO),is closely linked to increased risk of cardiovascular disease and fat deposition in mammals.Hens fed with rapeseed meal(RSM)suffered from fatty liver hemorrhage syndrome(FLHS).This study was conducted to investigate whether RSM-induced fatty liver is due to TMAO via altering microbiota composition and diversity.At 33 weeks of age,600 laying hens were randomly divided into 5 treatment groups,namely control and 14%RSM treatment groups(DY5,with 16.2% erucic acid [EA]and 74.66% glucosinolate[Gl]contents;MB1,with 3.50% EA and 43.23 %Gl contents;DY6,with 6.7% EA and 22.67% Gl contents;XH3,with 44.60% EA and 132.83% Gl contents)for 8 weeks.Results revealed that 3 hens died due to liver hemorrhage after ingesting 14% RSM diet.The 14% RSM decreased serum low-density lipoprotein cholesterol(LDL-C)content(P<0.01)while tended to increase serum TMAO content compared to the control group(P=0.08).The 14% RSM diet increased red oil O optical density(P<0.01),and increased total cholesterol(TC)and LDL-C content in the liver(P<0.01,and P<0.01,respectively).The 14%RSM decreased liver total bile acid(TBA)content compared to the control(P<0.01).The DY6 had a higher TBA content in the liver than the XH3(P<0.01).The 14%RSM decreased mRNA abundance of liver X receptors alpha(LXR-α,P=0.01),and increased mRNA abundance of sterol response element binding protein 2(SREBP-2,P=0.04).Results revealed that the in-feed RSM could alter richness and diversity of cecal microbiota compared to the control(P<0.05).Liver TC content and serum TMAO showed a negative relationship with Proteobacteria and Actinobacteria(P=0.04).In conclusion,14%RSM increased liver TC and induced high liver score of FLHS,which was possibly associated with the altered cecal microbiota composition,increased serum TMAO levels and LXR-αand SREBP-2 expressions.Liping Zhu Jianping Wang Xuemei Ding Shiping Bai Qiufeng Zeng Yue Xuan Gregory S.Fraley Keying Zhang 2021Animal Nutrition2021,,4:2
15Eosinophilic gastroenteritis:Clinical manifestations and morphological characteristics,a retrospective study of 42 patients显示文摘Li Zhang Liping Duan Shigang Ding 0,,:1
16Molecular profiling of Bacteroides spp. in human feces by PCR-temperature gradient gel electrophoresis显示文摘Xiaoyan Pang Dezhong Ding Guifang Wei Meiling Zhang Linghua Wang Liping Zhao 2004Journal of Microbiological Methods2004,,3:1
17Twisted intra-molecular electron transfer phenomenon of dansyl immobilized on chitosan film and its sensing property to the composition of ethanol-water mixtures显示文摘Ding Liping Fang Yu Jiang Linling 2005Thin Solid Films2005,478,12:1
18Immobilization of pyrene on quartz plate surface via a flexible long spacer and its sensing properties to dicarboxylic acids显示文摘A novel photo-induced luminescence film has been prepared by immobilizing pyrene on quartz plate surface via a flexible long spacer, 1,3-diaminopropane and 3-glycidoxypropyl trimethoxysilane. The film shows combined monomer and excimer emission of pyrene in both wet and dry states. Steady-state and time-resolved fluorescence emission meas-urements demonstrated that the excimer emission mainly came from direct excitation of ground state dimers, and/or monomers in aggregated state. Classical Birks?scheme plays little role in the formation of the excimers. The structures of the excimers formed during the excitation are complex. Both standard excimer of sandwich-like fully overlapped structure and distorted ex-cimer of partially overlapped structure exist in the excited state of the fluorophore. The emission of the film is sensitive to the presence of dicarboxylic acids, including ethanedioic acid, malonic acid, succinic acid, etc. The emission in the monomer and excimer region increases along with increasing the concentration of the dicarboxylic acids. The time needed for the emission to reach equilibrium depends on the nature of the acids. It has been shown that the longer the chain length of the acids, the more the time needed. This observation is explained by considering the conformational reorganization of the immobilized pyrene due to insertion of the dicarboxylic acids into the space between neighboring spacers. Experimental results from similar studies using formic acid and acetic acid are in support of this explanation. Furthermore, the response of the film to dicarboxylic acids is reversible.GAO Lining FANG Yu Lü Fengting DING Liping 2004Science China Chemistry2004,47,3:1
19Study on the surface-modification of nano-hydroxyapatite with lignin and the corresponding nanocomposite with poly (lactide-co-glycolide)显示文摘To obtain nano-hydroxyapatite/poly(lactideco-glycolide)(n-HA/PLGA)nanocomposite with superior mechanical properties,here,lignin was chosen to surfacemodify for n-HA through co-precipitation method.The different reaction conditions of reaction time,phosphorus source,and the lignin addition amount were studied by fourier transformation infrared spectra,X-ray diffraction,the intuitionistic dispersion experiment,transmission electron microscope and thermal gravimetric analysis.The reaction mechanism and the best appropriate reaction condition were obtained.More importantly,the results of electromechanical universal tester,scanning electron microscope,differential scanning calorimetric analyzer,polarized optical microscopy and dynamic mechanical analysis confirmed that the obtained n-HA could greatly increase the mechanical strength of PLGA,owing to the excellent dispersion and promotion crystallization effect.Moreover,in vitro cell culture experimental results indicated that the n-HA surface-modified by lignin was favorable to improve the cell biocompatibility of PLGA.The study suggested that the introduction of lignin was a novel method to acquire a highly dispersed n-HA,which would provide a new idea to achieve the n-HA/PLGA nanocomposite as bone materials in future,and it would pave the way towards a new application of lignin in biomedical field.Haojie Ding Liuyun Jiang Chunyan Tang Shuo Tang Bingli Ma Na Zhang Yue Wen Yan Zhang Liping Sheng Shengpei Su Xiang Hu 2021Frontiers of Chemical Science and Engineering2021,15,3:1
20Catalytic activities of CuO/TiO2 and CuO-ZrO2/TiO2 in NO+CO reaction显示文摘JIANG Xiaoyuan DING Guanghui LOU Liping 2004Journal of Molecular Catalysis:Chemical2004,218,:1
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