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determination of riding comfort on cycleways using a smartphone application

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 747-760页

作者： Anna Niska Leif sj?gren Peter Andrén Christian Weber Tineke de Jong Aslak Fyhri department of Infrastructure Maintenance Swedish National Road and Transport Research Institute (VTI) department of Safety and Behavior Institute of Transport Economics

Well maintained cycleways will encourage more people to cycle, as the condition of cycleways is important for the safety, accessibility and riding comfort of cyclists. despite that, only a few models used to describe the quality of service for cyclists take the surface condition into account. Objective measuring methods are needed to enable reliable and effective assessment of surface conditions, and measurable performance criteria related to the needs of cyclists should be developed. The purpose of this study has been to test the reliability and validity of using accelerometers in smartphones to assess the riding comfort on cycleways. A smartphone application converting three-dimensional accelerometer measurements into a single indicator for cycleways has been used to assess road surfaces in two field studies, in Sweden and Norway, respectively. Both studies assessed test sections of varying quality. To relate the measurements to subjective riding comfort assessments by cyclists, recruited cyclists collected quantitative data using the app, whilst also rating their perceived riding comfort by completing a survey. Measurements were also related to standard road surface condition indicators, generated from a road surface tester equipped with 19 laser sensors: international roughness index(IRI), mega-and macrotexture. The results show that it is possible to describe the unevenness of a cycleway using the technology present in smartphones. A software application can be used to collect and analyse data from the acceleration sensors in the phone, which can then be used to describe the riding comfort of cyclists. It is mainly the unevenness in the 50-1000 mm sizerange that create the greatest discomfort for cyclists, and intermittent vibrations are perceived as more uncomfortable than more evenly distributed vibrations. Therefore, IRI is not a relevant measurement for describing the riding comfort of cyclists.

关键词： Cyclist Comfort Assessment Road surface measurement Smartphone application

Cancer-associated fibroblasts express CD1d and activate invariant natural killer T cells under cellular stress

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Cellular & Molecular Immunology 2024年第1期21卷 91-94页

作者： Shengduo Pei Jonas sjölund Yueyun Pan Kristian Pietras Mikael C.I.Karlsson department of Microbiology Tumor and Cell BiologyKarolinska InstitutetStockholmSweden Division of Translational Cancer Research Department of Laboratory MedicineLund University Cancer CentreLund UniversityLundSweden

Invariant natural killer T(iNKT)cells are part of the family of unconventional T cells,and they recognize glycolipid antigens presented on the MHC class I like molecule CD1^([1]).In humans there are five CD1 molecules named CD1a to CD1e,whereas mice use only CD1d for lipid ***,iNKT cells can elicit both cytotoxicity similarly to conventional CD8 T cells and secrete cytokines that influence the adaptive immune response including providing direct T cell help to B cells^([2]).In the context of tumors,they can use both release of granzyme B and use Fas-mediated mechanisms for killing of tumor *** iNKT cells use a restricted TCR repertoire and CD1 molecules are non-heterogenous the risk of graft vs host disease is limited and thus these T cells have been an attractive option for off the shelf immunotherapy to treat cancer^([3]).

关键词： killer CD1d Cancer

Electrochemical reduction process of bilirubin in dimethylformamide

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Chinese Journal of Chemistry 1995年第4期13卷 289-298页

作者： NIU, JJ DONG, sj CHINESE ACAD SCI CHANGCHUN INST APPL CHEMELECTROANALYT CHEM LABCHANGCHUN 130022PEOPLES R CHINA

The electrochemical reduction behavior of bilirubin (BR) at platinum electrode in DMF was investigated by cyclic voltammetry, in situ electron spin resonance spectroscopy and in situ rapid scanning thin layer spectroelectrochemistry. Experimental results revealed that the reduction of BR firstly undergoes an ECE process: GRAPHICS The generated (BR)(2)(3-). can be re-oxidized to BR and then to purpurin (Pu) by a series of oxidation processes: GRAPHICS However, the re-reduction reactions of Pu are not the reverse processes. The different reduction mechanisms are discussed in detail.

关键词： BILIRUBIN BILIVERDIN PURPURIN SPECTROELECTROCHEMISTRY BIOELECTROCHEMISTRY

SYNTHESIS　OF　BLOCK　COPOLYMERS　OF　STYRENE　AND　N－（p－SUBSTITUTED　PHENYL）　MALEIMIdeS　BY　ANIONIC　POLYMERIZATION

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Chinese Chemical Letters 1996年第4期7卷 367-370页

作者： Xu, sj Qiu, KY BEIJING UNIV COLL CHEM & MOL ENGNBEIJING 100871PEOPLES R CHINA

The block copolymers were synthesized by anionic pohymerization via two steps reaction. First, styrene was initiated by n-butyl lithium, then maleimides were added into the living styrene system to obtain block copolymers. 1H-NMR and FT-IR measurements indicated that block coplymers bad been formed From the esults of thermogravimetric, it could be concluded that the block copolymer had a much better thermal stability than random copolymers predared by radical polymerization. Also the surface hydrophilicities of the two kinds of copolymers were compared.

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Phase Structure Change of Mo-Si System duringMechanical Alloying

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Journal of Materials Science & Technology 1999年第5期15卷 423-426页

作者： Liu, sj Qu, XH Liu, ZJ Huang, BY Cent S Univ Technol State Key Powder Met Changsha 410083 Peoples R China

The structure of Mo-15.16 Si, Mo-30 Si and Mo-36.3 Si (wt pct) elemental powder mixture during mechanical alloying was studied using electron microscopy and X-ray diffraction. It had been found that, in all the systems under study, silicon disappeared initially during mechanical alloying (MA). In the Mo-Si systems all products were in form of amorphous state after long time milling, but there were different intermediate products. MoSi2 and Mo5Si3 intermetallic compounds in the Mo-30Si and Mo-36.3Si (wt pct) were directly synthesized from elements through inter-diffussion process. The high density of defects and interface of nano-crystal lines induced by ball milling would promote the reaction process. Only in the Mo-15.16Si (wt pct) system was Mo(Si) supersaturated solid solution formed as an intermediate product. Schematic free-energy diagram of Mo-Si system based on the thermodynamics was used to analyze the difference among the intermediate state products.

关键词： Molybdenum alloys

Substituent effects on chloro meso-tetra-ortho-alkylphenylporphinato iron catalyzed biomimetic oxidation of cyclohexane

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Chinese Journal of Chemistry 1995年第5期13卷 442-447页

作者： Zhu, sj Gui, MD Jiang, DX NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

Six sterically hindered chloro meso-tetra-ortho-alkylphenylporphinato irons (T(o-R)PPFe(III)Cl, R = Me, Et, n-Pr, i-Pr, n-Bu, t-Bu) were synthesized and used to catalyze the monooxygenation of cyclohexane with PhIO. Both the yields of cyclohexanol and the relative rates of monooxygenation of cyclohexane catalyzed by T(o-R) PPFe(IIl)Cl were higher than those of TPPFe(III)Cl respectively. The order of the yields(%) of cyclohexanol and the rate of cyclohexanol formation in the monooxygenation of cyclohexane catalyzed by T(o-R)PPFe(III)Cl for the different substituents are: i-Pr(58) > Et(57) > n-Pr(52) > Me(51) > n-Bu(48) > t-Bu(46) > H(35) and i-Pr > Et > t-Bu > n-PT greater than or equal to Me greater than or equal to n-Bu greater than or equal to H respectively. The special steric effect on the catalytic character of these different alkyl substituents in T(o-R)PPFe(III)Cl is proposed on the basis of the results.

关键词： chloro alkylphenylporphinato iron steric effect biomimetic catalysis

Effects of pigment glands and gossypol on somatic cell culture of upland cotton (Gos-sypium hirsutum L.)

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Chinese Science Bulletin 2001年第23期46卷 1975-1980页

作者： Zhu, sj Ji, DF Zhejiang Univ Fac Agr & Biotechnol Dept Agron Hangzhou 310029 Peoples R China

The effects of pigment glands and gossypol on the somatic cell culture of upland cotton were studied, using the materials as follows: three pairs of glanded and gland less upland cotton near isogenic lines, TM-1, and Coker 312. The results showed that the pigment glands and gossypol contents in the explants had great inhibiting effect on the induction and growth of callus in somatic cell culture of upland cotton, and the induction rate of callus and the single callus weight of glandless cotton were much higher than those of their glanded near isogenic lines. It was easier to obtain regeneration plants from glandless cotton than from their glandednear isogenic lines. There was a significant inverse correlation between the gossypol contents in the explants and callus induction rate, with the correlation coefficient of -0.84. The vitro gossypol in the medium had some inhibiting effect on the induction and growth of callus, especially for the gland-less cotton. However, a certain concentration of vitro

关键词： pigment gland gossypol G. hirsutum somatic cell cul- ture.

Synthesis and Luminescence Properties of Barium Fluorotungstate Phosphors

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Chinese Chemical Letters 1997年第7期8卷 643-644页

作者： Yang, sj Sun, JT Qin, ZB HUBEI NORMAL UNIV DEPT CHEMHUNGSHI 435002PEOPLES R CHINA WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

The investigation of the system BaF2-WO3 revealed the existence of a fluoro-tungstate formulated as Ba2WO3F4. The Ba2WO3F4 was prepared with the solid state reaction method. Under UV or X-ray excitation, Ba2WO3F4 exhibits a very strong blue-green emission peaking at 480 nm at room temperature. The luminescence properties are similar to those of the tungstate, especially MgWO4. The luminescence and energy transfer of tungstates are well known for a long time and was reviewed by Blasse([1]). But barium tungstate show only weak luminescence even down to liquid helium temperature([2]). We were surprised to find that Ba2WO3F4 is an efficient phosphor which can be practically used. In this paper, the preparation method and luminescence properties of Ba2WO3F4 phosphor were investigated. The relationship between the luminescent properties and crystal structure was discussed.

关键词： Ba nm

MANNICH REACTION ON 1,2-DIHYDRO-1-PYRROLIZINONE

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Chinese Chemical Letters 1996年第1期7卷 9-10页

作者： Wang, sj Liu, FS Zhang, SF SHENYANG PHARMACEUT UNIV SHENYANG 110015PEOPLES R CHINA

The aminomethylation of the title compound can occur at 2-C or 5-C when it undergoes Mannich reaction with different amines. With aliphatic secondary amines, the reaction occurs at 2-C of the ketone, whereas with arom...

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