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Clinical Study of Shentong Zhuyu Decoction Combined with Massage Therapy in the Treatment of Exertional Chronic Lumbar Muscle Strain
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作者 lijun HAN Pengjun QIN +2 位作者 Junbao KE Qiang YAO yongzhi li 《Medicinal Plant》 2024年第2期65-68,共4页
[Objectives]To explore the effects of Shentong Zhuyu decoction combined with massage therapy in the treatment of exertional chronic lumbar muscle strain.[Methods]Sixty-four cases of exertional chronic lumbar muscle st... [Objectives]To explore the effects of Shentong Zhuyu decoction combined with massage therapy in the treatment of exertional chronic lumbar muscle strain.[Methods]Sixty-four cases of exertional chronic lumbar muscle strain were randomly divided into two groups(32 cases each group).The patients in the control group only took celecoxib capsules,and those in the treatment group additionally took Shentong Zhuyu decoction combined with massage therapy.TCM syndrome score,lumbar function,hemorrheology index and clinical effect were compared between the two groups before and after treatment.[Results]After treatment,the TCM syndrome scores of lumbar distension/dull pain,tingling-like lumbago,adverse lateral turn,body weight loss,dark purple tongue,slow or astringent pulse,and Oswestry disability index(ODI)score in the treatment group were lower than those in the control group,and the levels of plasma viscosity,red blood cell aggregation index,platelet aggregation rate(PAG)and fibrinogen(Fib)were lower than those in the control group,showing statistical significance(P<0.05).The overall clinical effect distribution of the treatment group was better than that of the control group,and the difference was statistically significant(P<0.05).[Conclusions]Shentong Zhuyu decoction combined with massage therapy can effectively relieve the symptoms of patients with lumbago and improve the lumbar mobility function and hemorrheology,with obvious therapeutic effects in the treatment of exertional chronic lumbar muscle strain. 展开更多
关键词 Chronic lumbar muscle strain EXERTIONAL MASSAGE Shentong Zhuyu decoction
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Defect-induced electron rich nanodomains in CoSe_(0.5)S_(1.5)/GA realize fast ion migration kinetics as sodium-ion capacitor anode
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作者 Tianlin li Danyang Zhao +6 位作者 Binghui Du Qing Yin yongzhi li Xiaolan Xue Fuxiang Wei Jiqiu Qi Yanwei Sui 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期583-593,I0014,共12页
Optimizing charge migration and alleviating volume expansion in anode materials are the key to improve the electrochemical performance for sodium-ion storage devices.Herein,a hierarchical porous conducting matrix conf... Optimizing charge migration and alleviating volume expansion in anode materials are the key to improve the electrochemical performance for sodium-ion storage devices.Herein,a hierarchical porous conducting matrix confining defect-rich selenium doped cobalt dichalcogenide(CoSe_(0.5)S_(1.5)/GA)is constructed as a promising SICs anode based on the guidance of theoretical calculation analysis.The increased defect concentration significantly enhanced the disorder degree of the compound and presented electron aggregation around the S atoms,which effectively modulated the electronic structure,further enabling high rate and ultra-capacity sodium storage.Moreover,strong interfacial coupling could construct spatial constraint to alleviate volume expansion as well as maintain electrode integrity and stability.The CoSe_(0.5)S_(1.5)/GA electrode can deliver a high capacity of 310.1 mA h g^(-1)after 2000 cycles at 1 A g^(-1),and the CoSe_(0.5)S_(1.5)/GA//AC sodium ion capacitor can exhibit an outstanding energy density of 237.5 W h kg^(-1).A series of characterization and theoretical calculation convincingly reveal that the defect moieties can regulate the Na^(+)storage and diffusion kinetics,which prove that our defect manufacture coupling with space-confined strategy can provide deep insights into the development of high-performance Na^(+)storage devices. 展开更多
关键词 Sodium-ion capacitors Defect manufacture Electron accumulation Carrier kinetic
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Pre-training transformer with dual-branch context content module for table detection in document images
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作者 yongzhi li Pengle ZHANG +2 位作者 Meng SUN Jin HUANG Ruhan HE 《虚拟现实与智能硬件(中英文)》 EI 2024年第5期408-420,共13页
Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such... Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such as information extraction.However,because of the diversity in the shapes and sizes of tables,existing table detection methods adapted from general object detection algorithms,have not yet achieved satisfactory results.Incorrect detection results might lead to the loss of critical information.Methods Therefore,we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect detections.To better deal with table areas of different shapes and sizes,we added a dualbranch context content attention module(DCCAM)to high-dimensional features to extract context content information,thereby enhancing the network's ability to learn shape features.For feature fusion at different scales,we replaced the original 3×3 convolution with a multilayer residual module,which contains enhanced gradient flow information to improve the feature representation and extraction capability.Results We evaluated our method on public document datasets and compared it with previous methods,which achieved state-of-the-art results in terms of evaluation metrics such as recall and F1-score.https://github.com/Yong Z-Lee/TD-DCCAM. 展开更多
关键词 Table detection Document image analysis TRANSFORMER Dilated convolution Deformable convolution Feature fusion
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Research of an Efficient LED Lighting Driver Based on Boost-Buck Converter 被引量:1
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作者 Renbo Xu yongzhi li +1 位作者 lixin Zhong Jiaming liu 《Circuits and Systems》 2014年第6期153-159,共7页
Boost-Buck converter is widely used in LED lighting drivers. In this paper, Boost-Buck main circuit related characteristics are firstly discussed, and then a new Boost-Buck high power efficient double loop control str... Boost-Buck converter is widely used in LED lighting drivers. In this paper, Boost-Buck main circuit related characteristics are firstly discussed, and then a new Boost-Buck high power efficient double loop control strategy is built by adopting error amplifier and integrator control method. It is demonstrated that the new system has many advantages such as high efficiency, fast response, strong anti-interference, good stability after analyses and simulations of its working dynamic characteristics. 展开更多
关键词 LED LIGHTING BOOST-BUCK Double LOOP Control EFFICIENT and Stable
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Validated,Rapid and Sensitive HPLC-MS/MS Method for Determination of 7,4'-Dihydroxylflavone in Rat Plasma and Its Application to Preliminary Pharmacokinetics
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作者 Shibo Wang Panpan li +2 位作者 yongzhi li Jiaping Wang Yujuan li 《Journal of Beijing Institute of Technology》 EI CAS 2019年第4期731-738,共8页
A sensitive,specific and rapid high-performance liquid chromatography-electronic spray ionization-tandem mass spectrometric method was developed and validated for the determination of 7,4'-dihydroxylflavone(7,4... A sensitive,specific and rapid high-performance liquid chromatography-electronic spray ionization-tandem mass spectrometric method was developed and validated for the determination of 7,4'-dihydroxylflavone(7,4'-DHF)in rat plasma.Genistein(internal standard,IS)was added in the collected plasma samples and subsided together by a simple one-step protein precipitation using acetonitrile-methanol(1:1,v/v).Chromatographic separation was performed on an Agilent Zorbax XDB C18 chromatography column and gradient elution with the mobile phase consisting of methanol and 0.1%formic acid was used.The mass spectrometric detection was performed by negative ion electro-spray ionization in multiple selected reactions monitoring(MRM)mode,with the transitions of m/z 253.1→113.0 for 7,4'-DHF and m/z 268.9→158.8 for IS.The calibration curve has liner relationship over the concentration range of 0.1-50.ng/mL(r=0.995.4).The intra-and inter-day precision(RSD%)was less than 10%,and the accuracy(RE%,relative error)ranged from-5.2%to 8.0%.The fully validated method was applied to the pharmacokinetics(PK)of 7,4'-dihydroxylflavone(7,4'-DHF)in rat plasma after oral administration(two doses:15 and 30.mg/kg)and intravenous injection(5.mg/kg).The result showed that Tmax and Cmax was 1.33±0.29.h and 0.12±0.02.ng/mL(15.mg/kg),and 1.17±0.29.h and 0.17±0.04.ng/mL(30.mg/kg),respectively.The bioavailability was 0.078%(15.mg/kg)and 0.070%(30.mg/kg),respectively. 展开更多
关键词 7 4'-dihydroxylflavone HPLC-MS/MS PHARMACOKINETICS BIOAVAILABILITY
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A transformer generative adversarial network for multi-track music generation 被引量:4
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作者 Cong Jin Tao Wang +7 位作者 Xiaobing li Chu Jie Jiessie Tie Yun Tie Shan liu Ming Yan yongzhi li Junxian Wang Shenze Huang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第3期369-380,共12页
This study proposes a new generation network based on transformers and guided by the music theory to produce high-quality music work.In this study,the decoding block of the transformer is used to learn the internal in... This study proposes a new generation network based on transformers and guided by the music theory to produce high-quality music work.In this study,the decoding block of the transformer is used to learn the internal information of single-track music,and cross-track transformers are used to learn the information amongst the tracks of different musical instruments.A reward network based on the music theory is proposed,which optimizes the global and local loss objective functions while training and discriminating the network so that the reward network can provide a reliable adjustment method for the generation of the network.The method of combining the reward network and cross entropy loss is used to guide the training of the generator and produce high-quality music work.Compared with other multi-track music generation models,the experimental results verify the validity of the model. 展开更多
关键词 artificial intelligence deep learning MULTIMEDIA
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An Improved Non-isolated LED Converter with Power Factor Correction and Average Current Mode Control 被引量:1
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作者 Renbo Xu Hongjian li +1 位作者 yongzhi li Changqian Zhang 《Circuits and Systems》 2011年第3期242-248,共7页
A new type of high power LED drivers is proposed by adopting an improved two-stages non-isolated configuration. In order to improve power factor and achieve accurate average current control under universal input volta... A new type of high power LED drivers is proposed by adopting an improved two-stages non-isolated configuration. In order to improve power factor and achieve accurate average current control under universal input voltages ranging from 100 Vrms to 240 Vrms, the power factor correction and average current mode control methods operating in continuous current conduction mode are designed and implemented. With the LUMILEDS emitter type LEDs, a laboratory prototype is built and measured. And from the measured results, it could be concluded that the proposed driver has many better performances such as high power factor, low current harmonic, accurate average current control and switch protection. 展开更多
关键词 High POWER LED POWER Factor CORRECTION AVERAGE Current Mode Control
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Research on a High-Efficiency LED Driving Circuit Based on Buck Topology 被引量:1
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作者 Renbo Xu Hongjian li +1 位作者 yongzhi li Xiaomao Hou 《Circuits and Systems》 2011年第4期352-357,共6页
A high efficiency LED(Light Emitting Diode) driver based on Buck converter, which could operate under a wide AC input voltage range(85V^265V) and drive a series of high power LEDs, is presented in this paper. The oper... A high efficiency LED(Light Emitting Diode) driver based on Buck converter, which could operate under a wide AC input voltage range(85V^265V) and drive a series of high power LEDs, is presented in this paper. The operation principles, power loss factors of the LED driver in this study are analyzed and discussed in detail and some effective ways to improve efficiency are proposed through system design considerations. To verify the feasibility, a laboratory prototype is also designed and tested for an LED lamp which consists of 16 LUMILEDS LEDs in series. Experimental results show that a high efficiency of 92% at I0=350mA can be achieved and the studied driver might be practical for driving high power LEDs. In the last, the overall efficiency over 90% is gained through some experiments under variable input and output voltages and verifies the validity of the designed driver. 展开更多
关键词 LED DRIVER BUCK Type High Efficiency UNIVERSAL INPUT Voltage
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Graphene Oxide/Lauryl Betaine Nano Material Synthesis and Properties
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作者 Wang li Jing Jing +3 位作者 Zaixing Jiang Di Su yongzhi li Weihong Lu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2021年第2期8-20,共13页
This paper aims at synthesizing a detergent with graphene oxide(GO)and lauryl betaine(LB),where the GO will have a better performance with the modification of LB.First,the complexus of GO and LB and the complexus of G... This paper aims at synthesizing a detergent with graphene oxide(GO)and lauryl betaine(LB),where the GO will have a better performance with the modification of LB.First,the complexus of GO and LB and the complexus of GO,KH550(Amino functional silane),and LB were synthesized to obtain two products,GO⁃LB and GO⁃KH550⁃LB.Then,the abilities and safety of the products were evaluated by characterization,contact angle measurement,measurement of KRAFFT Point,foaming test,emulsion ability test,decontamination capacity test,skin irritation test,and skin allergy test.Results of the experiment showed that GO⁃LB was superior to GO⁃KH550⁃LB in wetting ability and foaming stability,while GO⁃KH550⁃LB outperformed in emulsifying capacity.Besides,good abilities of removing mussels,seaweed,and protein were proved.According to the result of the irritation test of the materials to skin,they were both at the light irritation level,and the irritation of the GO⁃LB was slightly lower than that of GO⁃KH550⁃LB.Neither GO⁃LB nor GO⁃KH550⁃LB had allergic effect.Therefore,it can be concluded that as a surface active agent,graphene oxide/lauryl betaine was effective as a new detergent,which had low irritation and insignificant allergic phenomena on the human body over a long term of use. 展开更多
关键词 graphene oxide lauryl betaine surfactivity skin irritation skin allergy
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Nanocrystalline High Entropy Alloys with Ultrafast Kinetics and High Storage Capacity for Large-Scale Room-Temperature-Applicable Hydrogen Storage
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作者 Long Luo Huimin Han +10 位作者 DianChen Feng Wei Lv liangpan Chen lirong li Tingting Zhai Suxia liu Shiyang Sun Yiming li Wenli Pei Junjie Cui yongzhi li 《Renewables》 2024年第2期138-149,共12页
High-entropy alloys(HEAs)are a promising solution for large-scale hydrogen storage(H-storage)and are therefore receiving increasing attention from the materials science community.In this study,we systematically invest... High-entropy alloys(HEAs)are a promising solution for large-scale hydrogen storage(H-storage)and are therefore receiving increasing attention from the materials science community.In this study,we systematically investigated the microstructures and H-storage properties of V_(35)Ti_(35)Cr_(10) Fe_(10)M_(10)(M=Mn,Co,Sc,or Ni)HEAs prepared by arcmelting.The cast HEAs were found to be nanocrystalline.The crystal lattice parameters and hydrogen absorption energies of the alloys were calculated using density functional theory(DFT)calculations.The alloys can be fully activated in just one cycle of hydrogen absorption/desorption under mild conditions,after which they reach hydrogen absorption saturation in approximately 100 s at ambient temperature.The hydrogenation kinetics of the HEAs are approximately five times higher than that of conventional solid-solution alloys with a body-centered cubic(BCC)structure.By performing in-situ hydriding differential scanning calorimetry in combination with DFT calculations,we revealed that the alloys are more susceptible to hydrogenation than traditional BCC structural alloys.The H-storage capacity of V_(35)Ti_(35)Cr_(10) Fe_(10)M_(10) alloys at ambient temperature was higher than that of HEAs reported in the literature.Quasi-in-situ X-ray diffraction characterization of the HEAs’hydrogenation revealed a phase transition process from a BCC to facecentered cubic,passing through a pseudo-BCC structure.Our work introduces a new perspective for designing alloys with ultrafast hydrogen absorption kinetics and high capacity for large-scale,room-temperature-applicable H-storage. 展开更多
关键词 high entropy alloys in-situ hydriding solid-state hydrogen storage nanocrystals kinetic properties
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Analysis of the Global Burden of Disease study highlights the trends in death and disability-adjusted life years of leukemia from 1990 to 2017 被引量:6
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作者 Zejin Ou Danfeng Yu +6 位作者 Yuanhao liang Wenqiao He yongzhi li Minyi Zhang Fangfei You Huan He Qing Chen 《Cancer Communications》 SCIE 2020年第11期598-610,共13页
Background:The patterns of leukemia burden have dramatically changed in recent years.This study aimed to estimate the global trends of leukemiarelated death and disability-adjusted life-years(DALYs)from 1990 to 2017.M... Background:The patterns of leukemia burden have dramatically changed in recent years.This study aimed to estimate the global trends of leukemiarelated death and disability-adjusted life-years(DALYs)from 1990 to 2017.Methods:The data was acquired from the latest version of the Global Burden of Disease(GBD)study.Estimated annual percentage changes(EAPCs)were calculated to estimate the trend of age-standardized rate(ASR)of death and DALYs due to leukemia and its main subtypes from 1990 to 2017.Results:Globally,the numbers of death and DALYs due to leukemia were 347.58×10^(3)(95%uncertainty interval[UI]=317.26×10^(3)-364.88×10^(3))and 11975.35×10^(3)(95%UI=10749.15×10^(3)-12793.58×10^(3))in 2017,with a 31.22% and 0.03% increase in absolute numbers from 1990 to 2017,respectively.Both of their ASR showed decreasing trends from 1990 to 2017 with the EAPCs being−1.04(95%confidence interval[CI]=(−1.10-−0.99)and−1.52(95%CI=−1.59-−1.44),respectively.Globally,the most pronounced decreasing trend of death and DALYs occurred in chronic myeloid leukemia with EAPCs of−2.76(95%CI=−2.88-−2.64)and−2.84(95%CI=−2.97-−2.70),respectively,while the trend increased in acute myeloid leukemia.The death and DALYs of leukemia decreased in most areas and countries with high socio-demographic index(SDI)including Bahrain,Finland,and Australia.Conclusions:The disease burden of death and DALYs due to leukemia decreased globally,and for most regions and countries from 1990 to 2017.However,the leukemia burden is still a substantial challenge globally and required adequate and affordable medical resources to improve the survival and quality of life of leukemia patients. 展开更多
关键词 disability-adjusted life year estimated annual percentage change global burden of disease LEUKEMIA number of death
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First detection of cutavirus DNA in stools of patients with rheumatic diseases in Guangzhou,China
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作者 yongzhi li liting Zheng +12 位作者 Huan He Husheng Xiong Jiaqi Chen Hengbiao Sun Caiyun Chen Qiushuang li Jiaqi Fu Fei Wu Yuhan Gao Juxian Xian Minyi liang Gang Xiao Qing Chen 《Virologica Sinica》 SCIE CAS CSCD 2023年第6期860-867,共8页
Cutavirus(CuV)is a novel protoparvovirus possibly associated with diarrhea and cutaneous T-cell lymphomas.Patients with rheumatic disease are immunosuppressed and may be more vulnerable to pathogenic viruses.A descrip... Cutavirus(CuV)is a novel protoparvovirus possibly associated with diarrhea and cutaneous T-cell lymphomas.Patients with rheumatic disease are immunosuppressed and may be more vulnerable to pathogenic viruses.A descriptive study was conducted among hospitalized patients with rheumatic diseases and individuals undergoing medical health check-ups between June 2019 and June 2022 in Guangzhou,China.Stool samples of subjects were tested for CuV DNA.Demographic and fecal examination data of patients were obtained from electronic medical records.A total of 505 patients with rheumatic diseases and 244 individuals who underwent medical health check-ups were included in the study.Of the patients with rheumatic disease,5.74%[95%confidence interval(CI):4.03%–8.12%]were positive for CuV DNA,while no individual in the medical health check-up group was positive,indicating a close correlation between CuV and rheumatic disease.Men and patients with rheumatoid arthritis or ankylosing spondylitis,according to the disease classification,were more susceptible to being infected with CuV(P<0.01).After adjustments,being male remained the only significant factor,with an adjusted odd ratio(OR)of 4.4(95%CI:1.7–11.4,P=0.002).Phylogenetic analysis of the CuV VP2 sequences showed three diverse clades,one of which was segregated to be a single branching independent of previously known sequences,which is possible a new genotype. 展开更多
关键词 Cutavirus(CuV) Rheumatic diseases PREVALENCE Risk factor Genetic characterization
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Dragon’s Blood Protect Rat Blood-Brain Barrier Dysfunction Induced by Simulated Microgravity Effect
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作者 Ranran Yan YuShi Zhang +4 位作者 yongzhi li JiaPing Wang Hajira Bibi Yu-lin Deng YuJuan li 《Space(Science & Technology)》 EI 2023年第1期487-495,共9页
Dragon’s blood(DB)has shown a protective effect on neurological diseases.Microgravity(MG)or simulated MG(SMG)can induce blood-brain barrier(BBB)dysfunction,which is a characteristic feature of neurological disorders.... Dragon’s blood(DB)has shown a protective effect on neurological diseases.Microgravity(MG)or simulated MG(SMG)can induce blood-brain barrier(BBB)dysfunction,which is a characteristic feature of neurological disorders.This study’s purpose was to evaluate the effect of DB on SMG-induced BBB dysfunction and explore its signaling pathway.Both DB and vitamin C(Vc)were administered orally for tail-suspended rats within 3 weeks.DB and Vc solutions were added to human brain microvascular endothelial cells(HCMEC/D3)cells,which were then exposed to SMG for 24 h.The protective effect of DB was assessed by hematoxylin and eosin and Nissl staining,ultrastructure observation,and permeability in rats.Cell apoptosis and the distribution of tight junction(TJ)and adherens junction(AJ)proteins and filamentous actin(F-actin)were examined in HCMEC/D3.The oxidative stress and inflammation,and TJ and AJ protein expressions were determined in rat brain and HCMEC/D3.The focal adhesion kinase(FAK)signaling pathway proteins were determined.DB protected SMG-induced rat BBB disruption by improving neuronal apoptosis,repairing widened intercellular space,and decreasing BBB permeability.DB effectively relieved SMG-induced HCMEC/D3 damage by inhibiting cell apoptosis and restoring F-actin spindle distribution.High doses of DB upregulated TJ and AJ protein expressions and decreased oxidative stress and proinflammatory cytokine levels in rat brain and HCMEC/D3.DB enhanced the expressions of FAK signal transduction proteins and F-actin/globular actin(G-actin)ratio in rat brain and HCMEC/D3,suggesting that DB promotes actin cytoskeleton polymerization,benefits the endothelial cell-cell and cell-extracellular matrix adhesion,and,in consequence,contributes to BBB integrity. 展开更多
关键词 BLOOD protective doses
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Efficient generation of third harmonics in Yb-doped femtosecond fiber laser via spatial and temporal walk-off compensation 被引量:4
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作者 Meng Zhang Yuxi Chu +5 位作者 Jun Zhao Dongyu Yan yongzhi li Genyu Bi Bowen liu Minglie Hu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第3期69-73,共5页
On the basis of a home-made femtosecond Yb-doped fiber laser, we designed a compact and efficient third harmonic generation scheme by a simple compensation plate of β-Ba B2O4 crystal. The compensation plate is optimi... On the basis of a home-made femtosecond Yb-doped fiber laser, we designed a compact and efficient third harmonic generation scheme by a simple compensation plate of β-Ba B2O4 crystal. The compensation plate is optimized through its thickness and cutting angle to reverse both spatial and temporal walk-off. By optimizing the parameters of the compensation plate and incident light intensity, a maximum output of 2.23 W with a repetition rate of 1 MHz at 345 nm is obtained, which implies a conversion efficiency of 23% from the infrared to ultraviolet. 展开更多
关键词 ultrafast nonlinear optics harmonic generation and mixing ULTRAVIOLET compensation plates
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An advanced five-unknown higher-order theory for free vibration of composite and sandwich plates 被引量:2
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作者 Zhen WU Rui MA +2 位作者 yongzhi li Yushan XIAO Jie MEI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第9期104-118,共15页
Accurate prediction of dynamic characteristics is quite critical to understand the strength of layered structures.Nevertheless,the existing five-unknown higher-order theories encounter difficulties to forecast accurat... Accurate prediction of dynamic characteristics is quite critical to understand the strength of layered structures.Nevertheless,the existing five-unknown higher-order theories encounter difficulties to forecast accurately the dynamic response of sandwich structures.Therefore,a new five-unknown higher-order theory is developed for free vibration analysis of composite and sandwich plates,which possesses the same degree of freedom as those of other five-unknown higherorder theories.The developed model can meet beforehand interlaminar continuity conditions and the free-surface conditions of transverse shear stresses.To assess capability of the proposed model,analytical solution for such composite structures with simply-supported conditions has been presented by employing Hamilton’s principle,which is utilized for analysis of mechanical behaviors of composite and sandwich plates.Compared with the three-dimensional(3 D)elasticity solutions,3 D finite element results and the results obtained from the chosen five-unknown higher-order models,the proposed model can yield accurately natural frequencies of composite and sandwich plates.Even for the thick plates,the higher-order frequencies calculated from the proposed model are in good agreement with the 3 D finite element results.By studying effect of the thickness/length ratios on natural frequencies,it is found that the proposed model is adaptable to predicting natural frequencies of the sandwich plates with the thickness/length ratios between 1/4 and 1/100.In addition,some factors influencing accuracy of five-unknown higher-order models have been investigated in detail.Finally,by means of numerical analysis and discussion,some conclusions have been drawn as well,which can serve as a reference for other investigators. 展开更多
关键词 Analytical solution Five-unknown Free vibrations Higher-order theory Sandwich plates
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Dual-channel microfluidic sensor based on side-hole fiber with two long-period fiber gratings
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作者 Yu Zhang yongzhi li +6 位作者 Chao liu Zhihai liu Yaxun Zhang Xinghua Yang Jianzhong Zhang Jun Yang libo Yuan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2020年第2期1-4,共4页
We propose and demonstrate a dual-channel microfluidic sensor based on a side-hole fiber(SHF)with two longperiod fiber grating(LPFG)structures.There are two air holes in the SHF,which are natural microfluidic channels... We propose and demonstrate a dual-channel microfluidic sensor based on a side-hole fiber(SHF)with two longperiod fiber grating(LPFG)structures.There are two air holes in the SHF,which are natural microfluidic channels.We fabricate two LPFGs(long-period gratings LPG-A and LPG-B)in the SHF with the resonance wavelengths of 1268.7 nm and 1385.8 nm,respectively.Results show that the refractive index sensitivities of LPG-A and LPG-B are?76.0 nm/RIU and?71.1 nm/RIU,respectively.One can measure the refractive index of liquid samples in two channels simultaneously.The proposed dual-channel microfluidic sensor has advantages of good linearity response,fluidic technology compatibility,and easy light input/output coupling and system integration,which helps the sensor to have a potential application in environmental detection and food safety detection. 展开更多
关键词 long-period GRATING OPTICAL FIBER SENSOR refractive INDEX measurement
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Impact of aperture on dynamic response of sandwich plates with aluminium face-sheets and PMI core based on an alternative finite element formulation and experiments
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作者 Zhen WU yongzhi li +3 位作者 Dongjian ZHANG Jie MEI Xiaohui REN Rui MA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第4期266-280,共15页
Apertures generally exist in the sandwich structures attributing to mechanical connection and lightweight, which might induce failure of such structures. Thus, it is required to realize the impact of aperture on mecha... Apertures generally exist in the sandwich structures attributing to mechanical connection and lightweight, which might induce failure of such structures. Thus, it is required to realize the impact of aperture on mechanical behaviors of sandwich structures. If transverse shear deformations are unable to be described accurately, the reasonable prediction of dynamic behaviors of the form-core sandwich plates with apertures will meet severe challenges due to a large difference of transverse shear modulus at the adjacent layers. Thereby, such issue is less studied by using the efficient models and experimental testing, so an alternative sinusoidal-type finite element formulation is to be proposed to precisely predict dynamic response of the form-core sandwich structures with apertures. The proposed finite element formulation can meet beforehand compatible conditions of transverse shear stresses at the interfaces of adjacent laminates. In order to appraise strictly capability of the proposed model, experimental tests on natural frequencies of three groups of specimens with different apertures have been carried out. Moreover, four specimens in each group are tested to reduce the testing errors, which is less reported in the published literature. In addition,three-dimensional Finite Element Method(3-D FEM) is also selected to account for the good performance of the present model. Finally, the impact of aperture diameter on the natural frequencies of the sandwich structures is both experimentally and numerically investigated, which can serve as a reference for other researchers. 展开更多
关键词 Dynamic response Sandwich plates Higher-order theory Experimental tests Finite element method
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Property of alumina to adsorb long chain normal-paraffinhydrocarbons
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作者 yongzhi li Xianliang Deng Weile Yu 《Chinese Science Bulletin》 SCIE EI CAS 1998年第2期126-128,共3页
That alumina can strongly absorb long chain normal_paraffin hydrocarbon was found when alumina was used in the preparative group_type separation of heavy petroleum fractions. The reason for the above property of alumi... That alumina can strongly absorb long chain normal_paraffin hydrocarbon was found when alumina was used in the preparative group_type separation of heavy petroleum fractions. The reason for the above property of alumina may be that the normal_paraffin hydrocarbons can extend closely on the alumina surface. One molecule of long chain normal_paraffin hydrocarbon can be adsorbed by many active sites of alumina surface. The longer chain normal_paraffin hydrocarbon can be adsorbed by more active sites of alumina surface; this results in the longer chain normal_paraffin hydrocarbon has a stronger adsorption on alumina. 展开更多
关键词 ALUMINA adsorption PROPERTY LONG CHAIN normal-paraffin hydrocarbons.
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