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A study on key technologies of unmanned driving 被引量:15
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作者 Xinyu Zhang Hongbo Gao +3 位作者 Mu Guo Guopeng Li yuchao liu Deyi Li 《CAAI Transactions on Intelligence Technology》 2016年第1期4-13,共10页
Although the development of machine intelligence is far from simulating all the cognitive competence of our brains, still it is absolutely possible to peel the driving activity from people's cognitive activities and ... Although the development of machine intelligence is far from simulating all the cognitive competence of our brains, still it is absolutely possible to peel the driving activity from people's cognitive activities and then make the machine finish some low-level, complicated and lasting driving cognition by simulating our brains. The goal of driving is to replace drivers and free them from boring driving activities. Based on some studies on unmanned driving, this paper summarizes and analyzes the background, significance, research status and key technology of unmanned driving and the research group also introduces some research on brain cognition of driving and sensor placement of intelligent vehicles, which offers more meaningful reference to push the study of unmanned driving. 展开更多
关键词 Unmanned driving Brain cognition of driving Sensor placement Formalization of brain cognition
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厨余物的“高光”时刻——从厨余垃圾到碳量子点的居家制备及应用探究 被引量:3
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作者 童新阳 葛子健 +2 位作者 刘煜超 姚奇志 李玲玲 《大学化学》 CAS 2022年第5期1-12,共12页
以生活中常见的苦瓜头、香蕉皮等厨余物为原料,通过对文献的系统优化,将新型荧光材料——碳量子点的制备,创新性地开发为居家实验,中小学生甚至幼儿园小朋友在家长指导下,在家中用简单厨具即可轻松做出碳量子点,绿色安全,观感愉悦,趣味... 以生活中常见的苦瓜头、香蕉皮等厨余物为原料,通过对文献的系统优化,将新型荧光材料——碳量子点的制备,创新性地开发为居家实验,中小学生甚至幼儿园小朋友在家长指导下,在家中用简单厨具即可轻松做出碳量子点,绿色安全,观感愉悦,趣味性强。同时,对居家碳量子点进行多色荧光调控、大型仪器表征和重金属离子检测等应用的探究,适合面向高中生、本科生开展源于生活的科普活动和综合实验。此外,就公众关心的量子、量子点等概念进行科学解读,辟谣“量子+生活”现象。本实验旨在以多种有趣形式开展梯度科普,生动诠释前沿概念,激发公众对厨余物资源化利用的热情,阐释化学来源于生活,又造福于生活的理念。 展开更多
关键词 碳量子点 居家实验 厨余物 梯度科普 重金属离子检测
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A multicenter randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of rhubarb in treating acute exacerbation of chronic obstructive pulmonary disease of the syndrome type phlegm-heat obstructing the lungs 被引量:1
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作者 Fengjie Zheng Yan Sun +6 位作者 Xianggen Zhong Yueqi Wang Ruohan Wu Miao liu yuchao liu Kuo Gao Yuhang Li 《Journal of Traditional Chinese Medical Sciences》 2016年第2期71-80,共10页
Objective:To observe the clinical efficacy and safety of oral administration of the traditional Chinese herb rhubarb to treat acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Method:This was a multi... Objective:To observe the clinical efficacy and safety of oral administration of the traditional Chinese herb rhubarb to treat acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Method:This was a multicenter randomized double-blinded placebo controlled study that took place in 7 provinces of China that enrolled 244 patients(aged 18e80 years)who had acute exacerbation of COPD with the traditional Chinese syndrome pattern of phlegm-heat obstructing lung.Participants were divided into experimental and control groups.The experimental group received 4.5 g of rhubarb granules twice daily and the control group received placebo granules.Both groups also received conventional Western therapy consisting of oxygen therapy,an antibiotic,expectorant,and a bronchodilator.Treatment lasted 10 days.Symptom scores for cough,sputum volume and color,wheezing and chest tightness before treatment and on days 3,5,7,and 10 during the treatment were recorded.Lung function,arterial blood gas and levels of serum inflammatory factors,interleukin-4(IL-4),interleukin-8(IL-8),and interleukin-10(IL-10)and tumor necrosis factor-alpha(TNF-a),before and after treatment were measured.Results:The sample size of the full analysis set(FAS)was 244 participants,and the sample size of per protocol set(PPS)was 235.Following 10 days’treatment,symptom scores of the experimental group were markedly lower than those of the placebo group(FAS:mean difference1.67,95%CI:e2.66 to0.69,P Z 0.001;PPS:mean difference1.55,95%CI:2.56 to0.54,P Z 0.003).Lung function in the experimental group was significantly higher than in the placebo group(FEV1,FAS:mean difference 0.12,95%CI:0.06 to 0.18;P<0.001;PPS:mean difference 0.12,95%CI 0.05 to 0.18;P<0.001.FVC:FAS:mean difference 0.16,95%CI:0.06 to 0.26;P Z 0.002;PPS:mean difference 0.16,95%CI 0.05 to 0.26;P Z 0.003.FEV1%,FAS:mean difference 5.95,95%CI:3.36 to 8.53;P<0.001;PPS:mean difference 5.92,95%CI 3.28 to 8.56;P<0.001.).PaO2,PaCO2,as well as serum inflammatory factors were also improved when compared to the placebo group.There were no significant differences in the incidence rate of adverse reaction between the two groups.Conclusions:Compared with placebo,rhubarb granules significantly reduced symptom scores,improved blood oxygen level,controlled systemic inflammatory response,without significant adverse effects.Thus,rhubarb may be a beneficial adjuvant method for treating the phlegm-heat obstructing the lung syndrome pattern of AECOPD. 展开更多
关键词 Traditional Chinese medicine COPD Phlegm-heat obstructing the lung syndrome RHUBARB Randomized controlled trial
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Bipolar Thermally Activated Delayed Fluorescence Emitter with Balanced Carrier Transport for High-Efficiency Nondoped Green Electroluminescent Devices
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作者 yuchao liu Zhagen Miao +5 位作者 Haikuo Gao Shian Ying Can Gao Shouke Yan Huanli Dong Zhongjie Ren 《CCS Chemistry》 CSCD 2024年第9期2346-2357,共12页
High-efficiency electroluminescent devices featuring simplified architecture have received considerable attention due to significant advantages in construction procedures and commercialized applications.However,there ... High-efficiency electroluminescent devices featuring simplified architecture have received considerable attention due to significant advantages in construction procedures and commercialized applications.However,there still remains a critical challenge with regard to the lack of organic semiconductors that simultaneously possess high luminescent efficiency and balanced carrier-transporting abilities.Herein,we design a thermally activated delayed fluorescence(TADF)emitter 4-(9,9-dimethyl-9,10-dihydroacridine)-4′-triphenylphosphineoxide-benzophenone(DMAC-BPTPO)by incorporating triphenylphosphine oxide into the donor–acceptor skeleton.The accessional electrontransporting moiety,rod-like dimer,and horizontally packing model synergistically enable DMAC-BP-TPO which possesses an excellent photoluminescence quantum yield of nearly 90%with a reverse intersystem crossing rate constant of 2.0×106 s−1,horizontal dipole ratio of 89%,and a balanced electron and hole mobilities with a small constrast ratio of 1.08.Eventually,simplified electroluminescent devices including organic lightemitting diodes(OLEDs)and organic light-emitting transistors(OLETs)incorporating DMAC-BP-TPO-based nondoped film are demonstrated due to their superior integrated optoelectronic properties along with preferable horizontal dipole orientation.A record-high external quantum efficiency value of 21.7%and 4.4%are finally achieved in the simplified nondoped OLED and OLET devices,which are among the highest values in the related research fields.This work provides a new avenue to develop a high-efficiency bipolar TADF emitter to advance the simplified electroluminescent devices. 展开更多
关键词 organic light-emitting diode organic lightemitting transistor BIPOLAR thermally activated delayed fluorescence nondoped active layer
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Realizing External Quantum Efficiency over 25% with Low Efficiency Roll-Off in Polymer-Based Light-Emitting Diodes Synergistically Utilizing Intramolecular Sensitization and Bipolar Thermally Activated Delayed Fluorescence Monomer 被引量:2
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作者 yuchao liu Yanchao Xie +4 位作者 Lei Hua Xingwen Tong Shian Ying Zhongjie Ren Shouke Yan 《CCS Chemistry》 CSCD 2023年第4期1005-1017,共13页
Since polymer-based light-emitting diodes(PLEDs)arewellsuited building blocks for large-area and low-cost flexible display equipment,state-of-the-art thermally activated delayed fluorescence(TADF)PLEDs are in high dem... Since polymer-based light-emitting diodes(PLEDs)arewellsuited building blocks for large-area and low-cost flexible display equipment,state-of-the-art thermally activated delayed fluorescence(TADF)PLEDs are in high demand.To respond to this demand,light-emitting TADF units have initially been modified with electron-transporting units to balance the carrier transport of regiorandom TADF polymers,and simultaneously,an intramolecular sensitizing strategy has also been employed by covalently incorporating TADF sensitizers with light-emitting TADF units and hosts in conjugated polymers to accelerate the spin-flip of triplet excitons.Superior photophysical properties have been achieved by a rational regulation of the proportions of each component,achieving a photoluminescence quantumyield of 90%,an extremely high rate of reverse intersystem crossing of 3×106 s−1,and a relatively low nonradiative decay rate of around 105 s−1.As a result,the solutionprocessed PLEDs can attain an external quantum efficiency(EQE)value of 25.4%with emission peaks of around 550 nm,representing record-high performance for PLEDs.The efficiency roll-off can also be significantly suppressed,maintaining an EQE value of 24.2%at 1000 cd/m2 with ideal efficiency roll-off of lower than 5%.Encouragingly,this work provides a valid strategy to tackle the imperative need for PLEDs with high EQE and low efficiency roll-off. 展开更多
关键词 thermally activated delayed fluorescence polymer light-emitting diodes intramolecular sensitizing strategy balanced carrier transports low efficiency roll-off
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Review on herbal tea as a functional food:classification,active compounds,biological activity,and industrial status 被引量:1
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作者 yuchao liu Chunyan Guo +5 位作者 Erhuan Zang Ruyu Shi Qian liu Min Zhang Keyong Zhang Minhui Li 《Journal of Future Foods》 2023年第3期206-219,共14页
Most herbal tea infusions use edible medicinal plants as raw material and are consumed daily.Although herbal tea has a long history of health care applications worldwide,there is a lack of systematic research on the c... Most herbal tea infusions use edible medicinal plants as raw material and are consumed daily.Although herbal tea has a long history of health care applications worldwide,there is a lack of systematic research on the classification and functional nutritional value of various herbal teas.In recent years,the discovery of the rich biological activities and health benefits of herbal tea has become a driving force for researchers interested in its development as a functional food.However,the shortcomings of herbal tea products are not fully known.In particular,the quality evaluation system is not perfect,and there is insufficient data on the mechanism of action of herbal teas in their traditional uses.To better understand the functions and mechanisms of various herbal teas,this article reviews the classification,effective chemical composition,main biological activities,and mechanism of action of herbal teas.Finally,the current advantages,limitations,and direction of future development of herbal tea are determined and discussed. 展开更多
关键词 Herbal tea Functional food products Natural active ingredients Biological activities Industrial status
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Constructing an efficient deep-blue TADF emitter by host-guest interactions towards solution-processed OLEDs with narrowband emission
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作者 Yanchao Xie Lei Hua +5 位作者 Zhi Wang Yuerong liu Shian Ying yuchao liu Zhongjie Ren Shouke Yan 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第3期826-836,共11页
High-efficiency thermally activated delayed fluorescence(TADF) emitters and corresponding well-designed solution-processed organic light emitting diodes(OLEDs) are presently attractive due to their potential for explo... High-efficiency thermally activated delayed fluorescence(TADF) emitters and corresponding well-designed solution-processed organic light emitting diodes(OLEDs) are presently attractive due to their potential for exploiting large-area flexible displays. In this context, we innovatively integrate 2,12-di-tert-butyl-5,9-dioxa-13b-boronaphtho [3,2,1] anthracene as the acceptor with 3,6-bis(3,6-di-tert-butylcarbazol-N-yl) carbazole as the donor to construct a rigid deep-blue emitter, TB-3t BuCz, which exhibits a narrow emission with full-width-at-half-maximum(FWHM) of 46 nm. TB-3t BuCz itself dispalys no TADF characteristics both in solution or in pure film states. However, the significant TADF behavior can be observed when TB-3t BuCz is doped with 2,6-DCzPPy host due to the formation of exciplex-like species in 2,6-DCzPPy/TB-3t BuCz system. It is also found that the discernible spin-flip of triplet excitons is feasible when the S1/T1states of the formed exciplex stay slightly lower than S1 and T1states of TB-3t BuCz for the other host/TB-3t BuCz systems. Eventually, thanks to the synergetic effect of rigid structure and favorable photophysical properties of TB-3t BuCz, the solution-processed OLEDs based on 2,6-DCzPPy/TB-3t BuCz as emitting layer has achieved the significantly improved external quantum efficiency(EQE) of 14.6% with suppressed efficiency roll-off.The CIE1931 coordinate of(0.158, 0.052) is typically in deep-blue region. Note that, this EQE value is among the highest echelon of solution-processed OLEDs with deep-blue emission by utilizing boron-containing TADF emitters. 展开更多
关键词 thermally activated delayed fluorescence oxygen-bridged cyclized boron host-guest interactions solution-processed OLEDs narrowband deep-blue emission
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Aggregation-induced narrowband isomeric fluorophores for ultraviolet nondoped OLEDs by engineering multiple nonbonding interactions
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作者 Yumiao Huo Haoyuan Qi +7 位作者 Shuyao He Jie Li Shuping Song Jichen Lv yuchao liu Ling Peng Shian Ying Shouke Yan 《Aggregate》 EI CAS 2023年第6期191-199,共9页
Traditional donor-acceptor type organic luminescent materials usually suffer from unfavorable spectral broadening and fluorescence quenching problems arising from strong inter/intra-chromophore interactions in aggrega... Traditional donor-acceptor type organic luminescent materials usually suffer from unfavorable spectral broadening and fluorescence quenching problems arising from strong inter/intra-chromophore interactions in aggregation state.Here,two ultraviolet carbazole-pyrimidine isomers(named o-DCz-Pm and m-DCz-Pm)with novel aggregation-induced narrowband phenomenon are constructed and systematic investigated by experiments and theoretical simulations.Benefitting from strengthened steric hindrance and multiple noncovalent interactions,the nonradiative decay,vibrational motion,and structural relaxation of singlet state can be effectively suppressed in aggregation state.Consequently,the electroluminescence peak of 397 nm,full width at half maximum of 21 nm and external quantum efficiency of 3.4%are achieved simultaneously in nondoped o-DCz-Pm-based device.This work paves an avenue toward the development of high-performance narrowband nondoped ultraviolet materials and organic light-emitting diodes. 展开更多
关键词 aggregation-induced narrowband carbazole-pyrimidine derivatives nonbonding interactions organic light-emitting diodes ultraviolet emission
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Correlation between lower gastrointestinal tract symptoms and quality of life in patients with stable chronic obstructive pulmonary disease 被引量:10
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作者 Yan Sun Fengjie Zheng +5 位作者 Yuhang Li Ruohan Wu yuchao liu Miao liu Jinchao Zhang Kuo Gao 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第5期608-614,共7页
OBJECTIVE:To explore correlations between the symptoms of constipation and abdominal distention and severity of chronic obstructive pulmonary disease(COPD)in patients with stable disease.METHODS:We studied 191 patient... OBJECTIVE:To explore correlations between the symptoms of constipation and abdominal distention and severity of chronic obstructive pulmonary disease(COPD)in patients with stable disease.METHODS:We studied 191 patients with stable COPD(according to defined criteria)in this cross-sectional study from four three-level class A Chinese medicine hospitals in China.We built an Epidata 3.0 database and performed statistical analysis with SPSS,version 17.0.We analyzed correlations between the frequency of lower gastrointestinal tract symptoms(constipation and abdominal distention)and scores for major pulmonary symptoms(cough,sputum and wheezing)based on the St.George's Respiratory Questionnaire(SGRQ),6-minute walking distance(6MWD)and frequency of acute exacerbations of COPD(AECOPD).RESULTS:In addition to their pulmonary symptoms,39.79%and 40.31%of study patients withstable COPD reported constipation and abdominal distention,respectively.Scores for major pulmonary symptoms(cough,sputum and wheezing),AECOPD and SGRQ values in patients with constipation and abdominal distention were significantly greater,and the 6MWD markedly shorter,than in those without them.According to Pearson's correlation analysis,there were strong correlations between these lower gastrointestinal tract symptoms and scores for pulmonary symptoms,SGRQ,6MWD and AECOPD.CONCLUSION:Lower gastrointestinal tract symptoms such as constipation and abdominal distention can adversely affect pulmonary symptoms,frequency of acute exacerbations and quality of life in patients with stable COPD. 展开更多
关键词 Chronic obstructive pulmonary disease Constipation Flatulence Quality of life Questionnaires
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