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Study on the possible molecular state composed of D^∗sD^¯s1 within the Bethe-Salpeter framework

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Chinese Physics C 2020年第9期44卷 40-52页

作者： Hong-Wei Ke Xiao-Hai liu xue-qian li School of Science Tianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China

Recently,a vector charmonium-like state Y(4626)was observed in the portal of D+sDs1(2536)−.This intrigues an active discussion on the structure of the resonance because it has obvious significance for gaining a better understanding on its hadronic structure that contains suitable inner ***,this observation concerns the general theoretical framework about possible structures of exotic *** the mass of Y(4626)is slightly above the production threshold of D+sDs1(2536)−,whereas it is below that of D^∗sD^¯s1(2536)with the same quark contents as that of D+sDs1(2536)−,it is natural to conjecture that Y(4626)is a molecular state of D^∗sD^¯s1(2536),as suggested in the *** or negating this allegation would shed light on the goal we are concerned *** calculate the mass spectrum of a system composed of a vector meson and an axial vector i.e.,D^∗sD^¯s1(2536)within the framework of the Bethe-Salpeter *** numerical results show that the dimensionless parameterλin the form factor,which is phenomenologically introduced to every vertex,is far beyond the reasonable range for inducing even a very small binding energyΔ*** implies that the D^∗sD^¯s1(2536)system cannot exist in the nature as a hadronic molecule in this ***,we may not be able to assume the resonance Y(4626)to be a bound state of D^∗sD^¯s1(2536),and instead,it could be attributed to something else,such as a tetraquark.

关键词： molecular states Bethe-Salpeter equation strong decay

Preconcentration of Ultra-trace Cadmium with Nanometer-size TiO_2 Colloid and Determination by GFAAS with Slurry Sampling

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Chinese Chemical Letters 2006年第7期17卷 933-936页

作者： Sha Hua qian xue Qin li Han liN Mei XIAO Hong Bing DENG Luo Jing XIANG College of Resource and Environmental Science Wuhan University Wuhan 430072

A novel method of ultra-trace Cd（Ⅱ） preconcentration with nanometer-size TiO2 colloid and determination by graphite furnace atomic adsorption spectrometry（GFAAS） with slurry sampling was first advanced in this paper. The adsorption efficiency of nanometer-size TiO2 colloid for ultra-trace Cd（Ⅱ） could reach above 96% in a short time when the pH value was between 5 and 6. Other problems were also studied, such as adsorption capacity, nanometer-size TiO2 colloid dosage, effect of coexistent ions. The detection limit（3σ） and the relative standard deviation （R.S.D） of this method were 4.46.103 μg/L and 1.30%（n=7）, respectively. The method was successfully applied to the analysis of environmental samples with recoveries between 93.8% and 96.4%.

关键词： Nanometer-size TiO2 colloid Cd(Ⅱ) GFAAS slurry sampling.

Weak decays ofΞ^((′))_(c)→Ξin the light-front quark model

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Chinese Physics C 2021年第11期45卷 34-44页

作者： Hong-Wei Ke Qing-Qing Kang Xiao-Hai liu xue-qian li School of Science Tianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China

Without contamination from the final state interactions,the calculation of the branching ratios of semileptonic decays Ξ^((′))_(c)→Ξ+e^(+)ν_(e) may provide further information about the inner structure of charmed ***,by studying such processes,one can better determine the form factors of Ξ_(c)→Ξ that can be further applied to relevant *** this study,we used the light-front quark model to carry out computations where the three-body vertex functions forΞ_(c) and Ξ are *** fit the new data of the Belle II,we re-adjusted the model parameters to obtain β_(s[sq])=1.07 GeV,which is 2.9 times larger than β_(ss)=0.366 *** value may imply that the ss pair in Ξ constitutes a more compact ***,we investigated the non-leptonic decays of Ξ^((′))_(c)→Ξ,which will be experimentally measured ***,our model will be tested in terms of consistency with the new data.

关键词： charmed baryon weak decay relativistic quark model

Revisiting the determining fraction of glueball component in f_(0) mesons via radiative decays of J/ψ

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Chinese Physics C 2021年第2期45卷 133-143页

作者： Xing-Dao Guo Hong-Wei Ke Ming-Gang Zhao liang Tang xue-qian li College of Physics and New Energy Xuzhou University of TechnologyXuzhou 221111China School of Science Tianjin UniversityTianjin 300072China Department of Physics Nankai UniversityTianjin 300071China College of Physics Hebei Normal UniversityShijiazhuang 050024China

QCD theory predicts the existence of glueballs,but so far all experimental endeavors have failed to identify any such *** remedy this discrepancy between QCD,which has proven to be a successful theory for strong interactions,and the failure of experimental searches for glueballs,one is tempted to accept the promising interpretation that the glueballs mix with regular qq states of the same quantum *** lattice estimate of the masses of pure 0++ glueballs ranges from 1 to 2 GeV,which is the region of the f_(0)*** many authors suggest that the f_(0) mesonic series is an ideal place to study possible mixtures of glueballs and *** this paper,following the strategy proposed by Close,Farrar and li,we try to determine the fraction of glueball components inf_(0)mesons using the measured mass spectra and the branching ratios of J/ψ radiative decays intof_(0)*** the pioneering papers by Close et al.,more than 20 years have elapsed and more accurate measurements have been done by several experimental collaborations,so it is time to revisit this interesting topic using new *** suppose f_(0)(500)and f_(0)(980)to be pure quark states,while for f_(0)(1370),f_(0)(1500)and f_(0)(1710),to fit both the experimental data of J/ψradiative decay and their mass spectra,glueball components are ***,the mass of the pure 0++ glueball is phenomenologically determined.

关键词： glueball f_(0) J/ψradiative decay

Detection of Shigella gyrA mutations and correlations between gyrA mutations and quinolones resistance

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Journal of Microbiology and Immunology 2005年第2期3卷 101-104页

作者： CHONG ZHEN WANG xue PING li xue QIN qian li SHaG qian Department of Microbiology and Parasitology Shanghai Medical College Fudan University ShanghaiP. R. China

118 clinical strains of Shigella were serotyped, in which 116 strains were tested to be S. flexneri. The susceptibilities of the S .flexneri strains to quinolones were measured by the disk-diffusion method. It was found that most S .flexneri strains were susceptible to norfloxacin and ciprofloxacin, but resistant to nalidixic acid. To study the correlation between gyrA mutations and quinolones resistance, a fragment within the gyrA gene was amplified by PCR. The SSCP （Single-Strand Conformation Polymorphism） analysis was applied to detect mutations in PCR products of different strains. The mutations were then confirmed by DNA sequencing. Altogether, two types of mutation were revealed, in which one type was single mutation （ C42-T）, and the other was double mutations （ C42-T and A54- G）. By statistical analysis, C42-T （encoding Ser83-keu substitution） was shown to have correlation with nalidixic-acid resistance in the clinical strains of Shigella, while A54-G （encoding Asp87-Gly substitution） was shown to have correlations with both norfloxacin resistance and ciprofloxacin resistance.

关键词： Shigella Quinolones resistance PCR-SSCP gyrA mutations

“一带一路”背景下中越跨境民族文化旅游合作开发问题研究

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贵州民族研究 2017年第3期38卷 173-177页

作者：钱学礼邵阳学院湖南邵阳422000

中越两国合作历史由来已久,近年来,在"两廊一圈"和"一带一路"的战略指导下,双方跨境旅游领域的合作不断推进。而从文化层面来看,中越边境地区的少数民族大都同根同源,文化上具有很强的融通性,形成了一条联系密切的跨境民族文化带。此外... 详细信息

中越两国合作历史由来已久,近年来,在"两廊一圈"和"一带一路"的战略指导下,双方跨境旅游领域的合作不断推进。而从文化层面来看,中越边境地区的少数民族大都同根同源,文化上具有很强的融通性,形成了一条联系密切的跨境民族文化带。此外,中越跨境地区汇聚了两国丰富的自然景观与少数民族文化资源,这为双方协同挖掘特色民族文化资源,并通过整体开发、合作共建机制转化为特色旅游资源,进而促进双方开展跨境民族文化旅游合作提供了新的契机。

关键词：一带一路跨境少数民族文化旅游合作

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福氏志贺菌感染豚鼠和HeLa细胞的毒力

复旦学报（医学版） 2004年第2期31卷 132-134,F004页

作者：钱雪琴李雪萍王重振钱利生复旦大学上海医学院病原生物学系上海200032

目的　研究福氏志贺菌感染豚鼠和HeLa细胞后细菌致病能力的差异 ,探讨痢疾的防治。方法　选用 2 8株福氏志贺菌感染豚鼠眼角膜 ,观察角膜结膜病变反应 ,并进行细胞学、细菌学、病理组织切片检查。然后再选出12株福氏志贺菌强毒株和两株... 详细信息

目的　研究福氏志贺菌感染豚鼠和HeLa细胞后细菌致病能力的差异 ,探讨痢疾的防治。方法　选用 2 8株福氏志贺菌感染豚鼠眼角膜 ,观察角膜结膜病变反应 ,并进行细胞学、细菌学、病理组织切片检查。然后再选出12株福氏志贺菌强毒株和两株弱毒株 ,通过噬斑形成实验 ,观察对HeLa细胞的侵袭能力。结果　 2 8株福氏志贺菌均在 3d之内引起豚鼠发病 ,但症状表现有差异 ,除 2株福氏志贺菌感染豚鼠后发病时间延长、症状轻微外 ,其余菌株则引起较为严重的角膜结膜炎 ,尤其在感染第 3天 ,出现最为典型的临床表现。噬斑形成试验结果与豚鼠感染试验基本相符。结论　检测福氏志贺菌的毒力可用HeLa细胞噬斑形成试验替代Sereny试验。利用Sereny试验和HeLa细胞噬斑形成试验鉴定出 2 6株福氏志贺菌的强毒株和 2株弱毒株。

关键词：福氏志贺菌感染豚鼠 HeLa细胞毒力角膜结膜炎

Exploring biomedical applications with silver and copper nanotechnology

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cMat 2024年第2期1卷 1-8页

作者： xue-qian li Shao-Lei Xie Hui-Dong Xie Meng-Qi Shen Zhen-Hui Ma Hu liu Key Laboratory of Green and High-end Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXiningChina School of Chemistry and Chemical Engineering Xi'an University of Architecture and TechnologyXi'anChina Lenfest Center for Sustainable Energy Columbia UniversityNew YorkUSA Department of Physics Beijing Technology and Business UniversityBeijingChina

The overuse and misuse of antibiotics has accelerated the emergence of bacterial resistance,making the treatment of common infections increasingly difficult and *** has led to a rise in infection rates,worsened patient outcomes,and heightened mortality *** response,researchers have been exploring new antimicrobial strategies,with metal nanomaterials of controllable shape and size gaining significant attention for their unique antibacterial *** these,silver(Ag)and copper(Cu)nanomaterials(NMs)stand out for their wide applications in biomedical materials due to their effective antimicrobial mecha-nisms when used as *** and Cu NMs,exemplifying metal biomaterials,showcase broad-spectrum antibacterial capabilities,durable antimicrobial effects,low toxicity,and reduced likelihood of developing drug ***,they are known to promote angiogenesis,making them exceptionally suitable for biomaterial *** review underscores the significance of Ag and Cu NMs in the biomedical sector,detailing their applications and the promising role they play as medical *** aim is to encourage further exploration and utilization of Ag and Cu NMs in biomaterials and industrial production sectors.

关键词： Ag nanomaterials biomaterial cell-biological activity Cu nanomaterials metal nanomaterials

Λb→Λl+l- in perturbative QCD

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Λb→Λl+l- in perturbative QCD