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Science China Chemistry 2021年第10期64卷 1709-1715页

作者： Xiao-Xu Liu Yang Li Xin Li F.Ekkehardt hahn Ying-Feng Han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China Institut fiir Anorganicshe und Analytische Chemie Westfalische Wilhelms-Universitat Munster Corrensstrasse 30 48149 MunsterGermany

Isolation of E-1,2-bis(4-bromophenyl)-1,2-diphenyl-ethylene from the E/Z isomer mixture obtained by a Mc Murry coupling reaction and reaction of this isomer with imidazole followed by N-alkylation with n Bu Br and anion exchange yielded the bisimidazolium tetraphenylethylene(TPE)derivative H_(2)-E-1(PF_(6))_(2).The reaction of H_(2)-E-1(PF_(6))_(2) with Ag_(2)O yielded the dinuclear metallarectangle[Ag_(2)(E-1)2](PF_(6))_(2) where the two bis-NHC donors E-1 bridge two silver *** of[Ag_(2)(E-1)2](PF_(6))_(2) leads to E/Z isomerization of the di-NHC ligand and formation of Z-1 in the mononuclear complex[Ag(Z-1)]PF_(6).Demetallation of the di-NHC ligand with NH_(4)Cl/NH_(4)PF_(6) yielded bisimidazolium salt H_(2)-Z-1(PF_(6))_(2).The unique isomerization of the E-TPE derivative into its Z-isomer via metal complex formation/irradiation/demetallation cannot be achieved by irradiation of the individual imidazolium *** emissive properties of the TPE complexes[Ag_(2)(E-1)2](PF_(6))_(2) and[Ag(Z-1)]PF_(6) have been investigated.

关键词： N-heterocyclic carbene tetraphenylethylene photochemical isomerization fluorescence EZI process

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纳米结构非晶合金材料研究进展

物理学报 2017年第17期66卷 109-125页

作者：冯涛 Horst hahn Herbert Gleiter 南京理工大学格莱特纳米科技研究所南京210094 Institute of Nanotechnology Karlsruhe Institute of TechnologyKarlsruhe 76021Germany

迄今为止,人类社会新技术的发展主要是基于各种晶体材料(如金属、半导体等)的应用.晶体材料的性能可以通过改变它们的微观缺陷结构和/或微观化学结构来调控,但这对于当前的非晶材料而言却是难以实现的.新型的纳米结构非晶材料可以通过... 详细信息

迄今为止,人类社会新技术的发展主要是基于各种晶体材料(如金属、半导体等)的应用.晶体材料的性能可以通过改变它们的微观缺陷结构和/或微观化学结构来调控,但这对于当前的非晶材料而言却是难以实现的.新型的纳米结构非晶材料可以通过引入大量的非晶/非晶界面来改变非晶材料的微观缺陷结构和/或微观化学结构,从而实现对其性能的调控.本文主要讨论了目前纳米结构非晶合金材料的研究进展,包括其制备方法、结构特征和新性能.通过利用这些新特性,有可能会开启一个基于非晶材料的新技术时代.

关键词：非晶合金界面纳米结构性能调控

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汤鸿霄教授倍受国际尊敬和钦佩

环境科学学报 2023年第12期43卷 I0004-I0005页

作者：赫尔曼·哈恩宋永会(翻译) Hermann H.hahn 德国国家科学与工程院海德堡科学院欧洲科学与艺术院中国环境科学研究院 German National Academy of Science and Engineering Heidelberg Academy of Sciences European Academy of Sciences and Arts

汤鸿霄,一位倍受尊敬的水质科学家和老师、中国工程院院士,以及许多影响深远的著作的作者,在他91岁的时候离开了我们.从此,不仅是水科学领域,国际科学界也失去了一位最重要的领导人和指路明灯.众所周知,他不仅是众多学生的爱戴之师,而... 详细信息

汤鸿霄,一位倍受尊敬的水质科学家和老师、中国工程院院士,以及许多影响深远的著作的作者,在他91岁的时候离开了我们.从此,不仅是水科学领域,国际科学界也失去了一位最重要的领导人和指路明灯.众所周知,他不仅是众多学生的爱戴之师,而且是水领域这个最真正意义上世界性科学社会的导师.

关键词：中国工程院院士指路明灯科学界世界性老师影响深远领导人

Acupuncture in diabetic peripheral neuropathy-neurological outcomes of the randomized acupuncture in diabetic peripheral neuropathy trial

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World Journal of Diabetes 2023年第12期14卷 1813-1823页

作者： Sebastian Hoerder Isabel Valentina Habermann Katrin hahn Gesa Meyer-Hamme Miriam Ortiz Weronika Grabowska Stephanie Roll Stefan N.Willich Sven Schroeder Benno Brinkhaus Joanna Dietzel Institute of Social Medicine Epidemiology and Health EconomicsCharitéUniversitätsmedizinBerlin 10117Germany Department of Neurology CharitéUniversitätsmedizinCharitéplatz 1Berlin 10117Germany HanseMerkur Center of Traditional Chinese Medicine at University Hospital Eppendorff Martinistr 52Hamburg 20246Germany

BACKGROUND Diabetic peripheral neuropathy(DPN)is a common complication of diabetes mellitus and can lead to serious *** strategies for pain control are available but there are few approaches that influence neurological deficits such as *** To investigate the effectiveness of acupuncture on improving neurological deficits in patients suffering from type 2 *** The acupuncture in DPN(ACUDPN)study was a two-armed,randomized,controlled,parallel group,open,multicenter clinical *** were randomized in a 1:1 ratio into two groups:The acupuncture group received 12 acupuncture treatments over 8 wk,and the control group was on a waiting list during the first 16 wk,before it received the same treatment as the other *** groups received routine *** parameters were evaluated after 8,16 and 24 wk and included neurological scores,such as an 11-point numeric rating scale(NRS)11 for hypesthesia,neuropathic pain symptom inventory(NPSI),neuropathy deficit score(NDS),neuropathy symptom score(NSS);nerve conduction studies(NCS)were assessed with a handheld point-of-care ***-two participants were *** NRS for numbness showed a difference of 2.3(P<0.001)in favor of theacupuncture group,the effect persisted until week 16 with a difference of 2.2(P<0.001)between groups and 1.8points at week 24 compared to *** NPSI was improved in the acupuncture group by 12.6 points(P<0.001)at week 8,the NSS score at week 8 with a difference of 1.3(P<0.001);the NDS and the TNSc score improvedfor the acupuncture group in week 8,with a difference of 2.0 points(P<0.001)compared to the control *** were persistent in week 16 with a difference of 1.8 points(P<0.05).The NCS showed no *** both groups only minor side effects were *** Study results suggest that acupuncture may be beneficial in type 2 diabetic DPN and seems to lead to a reductionin neurological *** serious a

关键词： Diabetic peripheral neuropathy Numbness Nerve conduction study Acupuncture

Catchment soils as a factor of trace metal accumulation in sediments of the reservoir Klingenberg(eastern Ore Mountains, Germany)

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Journal of Environmental Sciences 2019年第12期31卷 1-14页

作者： Jens hahn Christian Opp Raphael Ganzenmuller Anntke Ewert Birgit Schneider Nina Zitzer Gabriela Laufenberg Philipps-University of Marburg Working Group for Hydro-and Soil GeographyDeutschhausstr.1035037 MarburgGermany University of Leipzig Institute of GeographyPhysical GeographyJohannisallee 19a04103 LeipzigGermany Philipps-Uniuersity o/Marbitrg Mass SpectrometryMarbacher Weg 6-1035037 MarburgGermany

The release and accumulation dynamics of trace metals in soils and aquatic sediments were exemplarily investigated in the catchment area of the Reservoir Klingenberg(Germany).Catchment soils were examined for mobilizable and total concentrations of arsenic(As),cadmium(Cd),chrome(Cr),iron(Fe),manganese(Mn),nickel(Ni),lead(Pb),and zinc(Zn)and compared with trace metal quantities accumulated in riverbed and reservoir *** comparison of all samples showed relatively small variations of Cr(7.96–46.0 mg/kg),Fe(7.79–40.4 g/kg),and Ni(6.06–56.5 mg/kg),while stronger differences were found for As(11.2–164 mg/kg),Cd(0.14–30.5 mg/kg),Mn(0.08–1.84 g/kg),Pb(20.7–183 mg/kg),and Zn(69.1–916 mg/kg).The catchment soils were slightly enriched by Cd,Pb,and *** Cd and Zn were characterized by large mobilizable *** mean trace metal concentrations in riverbed sediments were higher than in catchment soils,while reservoir sediments accumulated the highest amounts of the analyzed *** enrichment of trace metals in reservoir sediments was generally determined by the sedimentation of fine particles,while the distribution of As,Fe,and Mn was additionally impacted by redox *** Cd and Zn,which in comparison were most enriched in riverbed and reservoir sediments,a significant release from soils by leaching processes was *** accumulation of As and Pb in reservoir sediments was influenced to a greater extent by soil erosion and by anthropogenic or chalcogen sources in the catchment.

关键词： Trace metals Exchangeable forms Soil Sediment Catchment Sources

Insights into the radial water jet drilling technology-Application in a quarry

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 236-248页

作者： Thomas Reinsch Bob Paap Simon hahn Volker Wittig Sidney van den Berg GFZ German Research Centre for Geosciences Telegrafenberg14473 PotsdamGermany TNO Sustainable Geo EnergyUtrechtThe Netherlands International Geothermal Centre-GZB Lennershofstr.14044801 BochumGermany Well Services Group Phileas Foggstraat 65NL-7825 AL EmmenThe Netherlands

In this context, we applied the radial water jet drilling(RJD) technology to drill five horizontal holes into a quarry wall of the Gildehaus quarry close to Bad Bntheim, Germany. For testing the state-of-the-art jetting technology, a jetting experiment was performed to investigate the influence of geological heterogeneity on the jetting performance and the hole geometry, the influence of nozzle geometry and jetting pressure on the rate of penetration, and the possibility of localising the jetting nozzle utilizing acoustic activity. It is observed that the jetted holes can intersect fractures under varying angles, and the jetted holes do not follow a straight path when jetting at ambient surface condition. Cuttings from the jetting process retrieved from the holes can be used to estimate the reservoir rock permeability. Within the quarry, we did not observe a change in the rate of penetration due to jetting pressure *** monitoring was partially successful in estimating the nozzle location. Although the experiments were performed at ambient surface conditions, the results can give recommendations for a downhole application in deep wells.

关键词： Acoustic monitoring Drilling performance Trajectory Permeability Rock properties Radial water jet drilling(RJD)

Auditory perceptual efficacy of nonlinear frequency compression used in hearing aids:A review

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Journal of Otology 2017年第3期12卷 97-111页

作者： Yitao Mao Jing Yang Emily hahn Li Xu Department of Radiology Xiangya Hospital Central South University Communication Sciences and Disorders Ohio University Communication Sciences and Disorders University of Central Arkansas

Many patients with sensorineural hearing loss have a precipitous high-frequency loss with relatively good thresholds in the low *** present paper briefly introduces and compares the basic principles of four types of frequency lowering algorithms with emphasis on nonlinear frequency compression(NLFC). A review of the effects of the NLFC algorithm on speech and music perception and sound quality appraisal is then provided. For vowel perception, it seems that the benefits provided by NLFC are limited, which are probably related to the parameter settings of the compression. For consonant perception, several studies have shown that NLFC provides improved perception of highfrequency consonants such as/s/and/z/. However, a few other studies have demonstrated negative results in consonant perception. In terms of sentence recognition, persistent use of NLFC might provide improved performance. Compared to the conventional processing, NLFC does not alter the speech sound quality appraisal and music perception as long as the compression setting is not too aggressive. In the subsequent section,the relevant factors with regard to NLFC settings, time-course of acclimatization, listener characteristics, and perceptual tasks are *** the literature shows mixed results on the perceptual efficacy of NLFC, this technique improved certain aspects of speech understanding in certain hearing-impaired listeners. Little research is available on speech perception outcomes in languages other than English. More clinical data are needed to verify the perceptual efficacy of NLFC in patients with precipitous high-frequency hearing loss. Such knowledge will help guide clinical rehabilitation of those patients.

关键词： Nonlinear frequency compression Hearing loss Hearing aids Speech perception Music perception

Pathologic etiology and predictors of malignancy in children with cervical lymphadenopathy

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World Journal of Pediatrics 2023年第3期19卷 283-287页

作者： Jee Woo Kim Jee Yeon Baek Ji Young Lee Sung Min Lim Ji-Man Kang Won Kee Ahn Seung Min hahn Jung Woo Han Chuh Joo Lyu Jong Gyun Ahn Department of Pediatrics Severance Children's HospitalYonsei University College of Medicine50-1 Yonsei-RoSeodaemun-guSeoul 03722South Korea Institute for Immunology and Immunological Diseases Yonsei University College of MedicineSeoulSouth Korea Division of Pediatric Hematology and Oncology Department of PediatricsYonsei University College of MedicineYonsei University Health SystemSeoulSouth Korea Department of Pediatric Hemato-Oncology Yonsei Cancer CenterYonsei University Health SystemSeoulSouth Korea

Cervical lymphadenopathy in children is a common disease entity that is accompanied by a variety of processes,ranging from benign disease to *** the cause of cer-vical lymphadenopathy in children is often benign[1-4],the presence of enlarged lymph nodes can cause anxiety to parents because of its association with *** should be considered for the histologic diagnosis of persistent or unex-plained cervical lymphadenopathy in ***,biopsy is an invasive examination method,and it is difficult to clinically determine whether biopsy is needed in children with unexplained cervical ***,clini-cians should be aware of the differential diagnosis of lymph node enlargement in children and should identify situations in which malignancy may be *** this study,we aimed to identify the etiology of pediatric cervical lymphadenopathy using biopsy and to analyze the risk factors associated with malignancy in children with cervical lymphadenopathy.

关键词： malignancy cervical diagnosis

Biophotonic sensors with integrated Si_(3)N_(4)-organic hybrid (SiNOH) lasers for point-of-care diagnostics

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Light(Science & Applications) 2021年第4期10卷 648-659页

作者： Daria Kohler Gregor Schindler Lothar hahn Johannes Milvich Andreas Hofmann Kerstin Lange Wolfgang Freude Christian Koos Institute of Photonics and Quantum Elearo nics(IPQ) Karlsruhe Institute of Technology(KIT)Engesserstrasse 576131 KarlsruheGermany lnstitute of Microstructure Technology(IMT) Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany Robert Bosch GmbH Robert-Bosch-Campus 171272 RenningenGermany lnstitute for Autom ation and Applied Informatics(IAI) Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Early and efficient disease diagnosis with low-cost point-of-care devices is gaining importance for personalized medicine and public health *** this context,waveguide-(WG)-based optical biosensors on the siliconnitride(Si_(3)N_(4))platform represent a particularly promising option,offering highly sensitive detection of indicative biomarkers in multiplexed sensor arrays operated by light in the visible-wavelength ***,while passive Si_(3)N_(4)-based photonic circuits lend themselves to highly scalable mass production,the integration of low-cost light sources remains a *** this paper,we demonstrate optical biosensors that combine Si_(3)N_(4)sensor circuits with hybrid on-chip organic *** Si_(3)N_(4)-organic hybrid(SiNOH)lasers rely on a dye-doped cladding material that are deposited on top of a passive WG and that are optically pumped by an external light *** of the devices is simple:The underlying Si_(3)N_(4)WGs are structured in a single lithography step,and the organic gain medium is subsequently applied by dispensing,spin-coating,or ink-jet printing processes.A highly parallel read-out of the optical sensor signals is accomplished with a simple *** our proof-of-concept experiment,we demonstrate the viability of the approach by detecting different concentrations of fibrinogen in phosphate-buffered saline solutions with a sensor-length(L-)-related sensitivity of S/L=0.16 rad nM^(-1)mm^(-1).To our knowledge,this is the first demonstration of an integrated optical circuit driven by a co-integrated low-cost organic light *** expect that the versatility of the device concept,the simple operation principle,and the compatibility with cost-efficient mass production will make the concept a highly attractive option for applications in biophotonics and point-of-care diagnostics.

关键词： passive waveguide pumped

A comparison of Guibourtia copallifera Benn. stands in South West Burkina Faso-community structure and regeneration

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Journal of Forestry Research 2012年第1期23卷 29-38页

作者： Assan Gnoumou Fidèle Bognounou Karen hahn Adjima Thiombiano Ougadougou University Department of plant Biology and Physiology03 PO Box 7021 Ouagadougou 03.OuagadougouBurkina Faso Institute For Ecology Evolution and DiversityJ.W.Goethe-UniversitySiesmayerstr.70.60323 Frankfurt/MAllemagne

Shifting agriculture, fire, and over exploitation of wood and copal resin are the major causes of Guibourtia copallifera Benn. vulner- ability in the south-west of Burkina Faso. Conservation of endangered species requires a thorough understanding of the dynamics of small populations. In the present study, we investigated the diversity and the dynamics of G copallifera communities in two different types of land use history, a protected area （stated forest of Como6-Leraba） and an unprotected area （the woodlands of Toumi and Timba）. A total of 17 rectangular plots （50 m × 20 m） were sampled in both protected and unprotected areas. All woody species were systematically identified, measured and classified into diameter and height classes. In the two different types of land use, the dynamics of G. copallifera＇s communities were good, and the diversities were similar and low with high β diversity.

关键词： biodiversity conservation shifting agriculture vulnerablespecies West Africa