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Chinese Journal of Polymer science 2011年第6期29卷 699-711页

作者： y.Mansoori s.shah sanaei s.V.Atghia M.R.Zamanloo Gh.Imanzadeh Department of Applied Chemistry Faculty of ScienceUniversity of Mohaghegh ArdabiliArdabil 56199-11367Iran

In this work, the syntheses of new thermally stable poly（amide-imide）s with pendant 2-pyridyl-l,3,4-oxadiazole units in n-butyl methyl imidazolium bromide as reaction media have been reported. A new dicarboxylic acid has been derived from the reaction of diamine, 2-（5-（3,5-diaminophenyl）-1,3,4-oxadiazole-2-yl）pyridine （POBD）, and trimellitic acid anhydride. Polymers were prepared from the reaction of the diimide-diacid （DIDA） and different aromatic diamines in butyl methyl imidazolium bromide, [bmim] [Br], in the presence of triphenyl phosphite （TPP） as condensing agent without needing any extra components. The prepared poly（amide-imide）s were characterized by FTIR, elemental analysis, and through the synthesis of a model compound. The prepared polymers were soluble in polar and aprotic solvents, such as DMF, DMsO, NMP and DMAc. The inherent viscosity of the polymer solutions was in the range of 0.52-1.33 dL/g measured in concentrated H2sO4 at a concentration of 0.125 g/dL at （25 ± 0.5）℃. The results are compared with the results obtained from common direct polycondensation with NMP as solvent. Polymers obtained in ionic liquid showed higher inherent viscosity than that of polymers obtained via classical method in NMP. Thermal properties of the polymers were studied with DsC and TGA methods.

关键词： Poly(amide-imide) Ionic liquid Polycondensation 1,3,4-Oxadiazole

Design and Implementation of a Driver's Eye state Recognition Algorithm Based on PERCLOs

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Chinese Journal of Electronics 2014年第4期23卷 669-672页

作者： PENG yan DONG yan CHENG du school of Management Capital Normal University Beijing Institute of Control Engineering

In order to improve the general detection accuracy of eye state, this paper puts forward an innovative method for judging human eye state based on PERCLOs. After pretreatment of the eye image, Hough transformation is used for ellipse detection and pupil position. The gray projection variance threshold analysis is then used to help make the final detection. Freeman chain and the snake model algorithm are used for the corner detection and precise calculation of the height of an open eye. Thus the PERCLOs value and the eye state can be figured out. The performance of our eye state recognition algorithm is validated by more than 1000 images within product database. The statistics result shows that the fatigue detection accuracy rate can meet the need of usage in complex environment.

关键词： Eye state detection Freeman chain code snake model Hough circle Ellipse detection

Insulin and leptin enhance human sperm motility, acrosome reaction and nitric oxide production

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Asian Journal of Andrology 2008年第5期10卷 799-807页

作者： Fanuel Lampiao stefan s. du Plessis Division of Medical Physiology Department of Biomedical Sciences University of Stellenbosch Tygerberg 7505 South Africa

Aim： To investigate the in vitro effects of insulin and leptin on human sperm motility, viability, acrosome reaction and nitric oxide （NO） production. Methods： Washed human spermatozoa from normozoospermic donors were treated with insulin （10 μIU） and leptin （10 nmol）. Insulin and leptin effects were blocked by inhibition of their intracellular effector, phosphotidylinositol 3-kinase （PI3K）, by wortmannin （10 μmol） 30 min prior to insulin and leptin being given. Computer-assisted semen analysis was used to assess motility after 1, 2 and 3 h of incubation. Viability was assessed by fluorescence-activated cell sorting using propidium iodide as a fluorescent probe. Acrosome-reacted cells were observed under a fluorescent microscope using fluorescein-isothiocyanate-Pisum sativum agglutinin as a probe. NO was measured after treating the sperm with 4,5-diaminofluorescein-2/diacetate （DAF-2/DA） and analyzed by fluorescence-activated cell sorting. Results： Insulin and leptin significantly increased total motility, progressive motility and acrosome reaction, as well as NO production. Conclusion： This study showed the in vitro beneficial effects of insulin and leptin on human sperm function. These hormones could play a role in enhancing the fertilization capacity of human spermatozoa.

关键词： insulin leptin spermatozoa nitric oxide motility acrosome reaction

A Bird’s Eye View of Quantitative Proteome of Tumor Tissues from Lung Cancer Patients by a High Precision Mass spectrometry Method

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Chemical Research in Chinese Universities 2024年第1期40卷 136-144页

作者： du Xiaohui LI Encheng WANG Qi yOU Xin Lung Cancer Transitional Medicine Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China Department of scientific Research Center The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China Department of Respiratory Medicine The Second Affiliated Hospital of Dalian Medical UniversityDalian116023P.R.China

Lung cancer produces a high incidence of malignant *** have been many studies on lung cancer using mass spectrometry(Ms)***,most studies have focused on humoral *** this work,26 pairs of tissue samples(tumor ***-tumor)from patients with lung cancer were analyzed using liquid chromatography-tandem Ms(LC-Ms/Ms)with data-independent acquisition *** total,3152 proteins were quantified from tissue samples with high confidence,including 189 up-regulated and 522 down-regulated proteins(tumor ***-tumor).In addition,79 and 690 proteins were identified only in para-cancerous samples and cancerous samples,*** results from bio-informatics tools indicated that altered proteins like PEBP1,HRG and LyZ could be ideal reservoirs for screening the potential biomarkers for lung *** is believed these tissue-specific proteomics results will assist in the studies of lung cancer.

关键词： Lung cancer Proteome Data-independent aquisition

Human’s digital footprints on the Qinghai-Tibet Plateau:Variations during festivals and impacts on nature reserves

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Journal of Geographical sciences 2021年第2期31卷 179-194页

作者： du yunyan TU Wenna LIANG Fuyuan yI Jiawei state Key Laboratory of Resources and Environmental Information system Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of sciences Beijing 100049China Department of Earth Atmosphericand Geographic Information SciencesWestern Illinois UniversityMacombIL61455USA

Mobile internet and wireless communication technologies have produced unprecedented location-aware *** big geospatial data can be used as a proxy measure of the‘digital footprints’left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine *** study investigated the spatiotemporal variations of human’s digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent’s location request *** results showed that human’s digital footprints cover less than 5%of Qinghai and Tibet,exhibiting either a U-shaped or an N-shaped temporal change pattern during the major *** changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and *** disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6%of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59,and the disturbance was significantly escalated during the National Day *** contrast,the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1%and 0.1,respectively.

关键词： digital footprint space-time variations human impact nature reserve location request

Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions

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Neural Regeneration Research 2025年第1期20卷 191-192页

作者： Narek Manukjan Daniel Fulton Zubair Ahmed WMatthijs Blankesteijn sébastien Foulquier Department of Pharmacology and Toxicology Maastricht UniversityMaastrichtThe Netherlands CARIM-school for Cardiovascular Diseases Maastricht UniversityMaastrichtThe Netherlands Neuroscience and Ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Centre for Trauma sciences Research University of BirminghamEdgbastonBirminghamUK MHeNs-school for Mental Health and Neuroscience Maastricht UniversityMaastrichtThe Netherlands Department of Neurology Maastricht University Medical CenterMaastrichtThe Netherlands

As the population ages,the burden of age-related diseases becomes ***,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common ***,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(csVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of *** term csVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CsVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018).

关键词： pathology becoming white

REsEARCH ON LAsER DIRECT DEPOsITION PROCEss OF Ti-6Al-4V ALLOy

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Acta Metallurgica sinica(English Letters) 2007年第3期20卷 171-180页

作者： s.y. Gao y.Z. Zhang L.K. shi B.L. du M.Z. Xi H.Z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

Laser direct deposition （LDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the LDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by LDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the LDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

Ren-integrable and ren-symmetric integrable systems

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： s y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is ***-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so *** and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for *** particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable *** examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry

面向BORO和BOPs的零售商退货策略与渠道决策

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管理工程学报 2025年第1期39卷 271-284页

作者：毛照昉苗琪琪杨哲杜泽霖天津大学管理与经济学部天津300072

消费者体验需求的提升促使零售商不断探索新渠道模式,以提高原有实体店效益的同时优化线上经营策略。本文分别考虑传统BORO(buy online and return online)和开通BOPs(buy online and pickup in store)两种渠道情形,构建零售商针对消费... 详细信息

消费者体验需求的提升促使零售商不断探索新渠道模式,以提高原有实体店效益的同时优化线上经营策略。本文分别考虑传统BORO(buy online and return online)和开通BOPs(buy online and pickup in store)两种渠道情形,构建零售商针对消费者线上购买并在线上或线下退款的差异化退货策略利润模型,分析两种渠道情形下的最优定价和最优退货策略,进而考虑BOPs渠道的溢出效应,分析零售商在相同退货策略下是否应该开通BOPs渠道。结果表明:(1)在两种情形下,随着线下商店数量的增多,零售商均会倾向于在低开店成本下选择全额退款策略,倾向于在高开店成本下选择部分退款策略;(2)在同渠道情形下,全额退款策略的定价始终低于部分退款策略。在同退货策略下,BOPs情形下的定价始终低于BORO情形;(3)高溢出效应和多商店数量都促使零售商选择开通BOPs渠道,但商店数量决定了BOPs线下麻烦成本规模因子对零售商开通BOPs渠道起推动还是抑制作用。本文为既定商店数量下多渠道零售商退货策略与渠道选择提供了决策支持。

关键词：商店数量 BORO BOPs 退货策略渠道选择

Rate constants for the reaction of ozone with n-butyl, s-butyl and t-butyl methyl sulfides

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Chinese science Bulletin 2008年第23期53卷 3620-3625页

作者： WANG Kun du Lin GE MaoFa Beijing National Laboratory for Molecular sciences (BNLMs) and State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of the Chinese Academy of sciences Beijing 100039 China

The rate constants for the ozone reactions with n-butyl methyl sulfide (n-BMs, CH3CH2CH2CH2sCH3), sec-butyl methyl sulfide (s-BMs, CH3CH2(CH3)CHsCH3) and tert-butyl methyl sulfide (t-BMs, (CH3)3CsCH3) were measured using our smog chamber under supposedly pseudo-first-order conditions at 300±2 K and 760 Torr. The experimental determined rate constants for n-butyl, s-butyl and t-butyl methyl sulfide are (1.23 ± 0.06)×10-19, (5.08 ± 0.19)×10?20 and (2.26 ± 0.14)×10?20 cm3·molecule-1·s-1, respectively. The reactivity-structure relationship of the reactions was discussed and used to illustrate the mechanism of the ozone reaction with thioethers. The results enrich the kinetics data of atmospheric chemistry.

关键词：丁基甲基硫化物臭氧动力学