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Welding Deviation Detection Algorithm Based on Extremum of Molten Pool Image Contour

Chinese Journal of Mechanical Engineering 2016年第1期29卷 74-83页

作者： ZOU Yong jiang lipei li Yunhua XUE Long huaNG Junfen huaNG Jiqiang College of Automation Science and Electrical Engineering Beihang University Optical Electromechanical Equipment Technology Key Laboratory of Beijing Beijing Institute of Petrochemical Technology

The welding deviation detection is the basis of robotic tracking welding, but the on-line real-time measurement of welding deviation is still not well solved by the existing methods. There is plenty of information in the gas metal arc welding（GMAW） molten pool images that is very important for the control of welding seam tracking. The physical meaning for the curvature extremum of molten pool contour is revealed by researching the molten pool images, that is, the deviation information points of welding wire center and the molten tip center are the maxima and the local maxima of the contour curvature, and the horizontal welding deviation is the position difference of these two extremum points. A new method of weld deviation detection is presented, including the process of preprocessing molten pool images, extracting and segmenting the contours, obtaining the contour extremum points, and calculating the welding deviation, etc. Extracting the contours is the premise, segmenting the contour lines is the foundation, and obtaining the contour extremum points is the key. The contour images can be extracted with the method of discrete dyadic wavelet transform, which is divided into two sub contours including welding wire and molten tip separately. The curvature value of each point of the two sub contour lines is calculated based on the approximate curvature formula of multi-points for plane curve, and the two points of the curvature extremum are the characteristics needed for the welding deviation calculation. The results of the tests and analyses show that the maximum error of the obtained on-line welding deviation is 2 pixels（0.16 ram）, and the algorithm is stable enough to meet the requirements of the pipeline in real-time control at a speed of less than 500 mm/min. The method can be applied to the on-line automatic welding deviation detection.

关键词： welding deviation welding seam tracking molten pool contour curvature extremum gas metal arc welding(GMAW)

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Competitive sorption between 17α-ethinyl estradiol and bisphenol A/4-n-nonylphenol by soils

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Journal of Environmental Sciences 2013年第6期25卷 1154-1163页

作者： Jianzhong li Lu jiang Xi Xiang Shuang Xu Rou Wen Xiang liu School of Environment Tsinghua University

The sorption of 17α-ethinyl estradiol （EE2）, bisphenol A （BPA）, and 4-n-nonylphenol （NP） in single systems and the sorption of EE2 with different initial aqueous concentrations of BPA or NP were examined using three soils. Results showed that all sorption isotherms were nonlinear and fit the Freundlich model. The degree of nonlinearity was in the order BPA （0.537-0.686）〉 EE2 （0.705-0.858）〉 NP （0.875-0.0.951） in single systems. The isotherm linearity index of EE2 sorption calculated by the Freundlich model for Loam, Silt Loam and Silt increased from 0.758, 0.705 and 0.858, to 0.889, 0.910 and 0.969, respectively, when BPA concentration increased from 0 to 1000 μg/L, but the effect of NP was comparably minimal. Additionally, EE2 significantly suppressed the sorption of BPA, but insignificantly suppressed that of NE These findings can be attributed to the difference of sorption affinity of EE2, NP and BPA on the hard carbon （e.g., black carbon） of soil organic matter that dominated the sorption in the low equilibrium aqueous concentration range of endocrine-disrupting chemicals （EDCs）. Competitive sorption among EDCs presents new challenges for predicting the transport and fate of EDCs under the influence of co-solutes.

关键词： competitive sorption 17α-ethinyl estradiol endocrine-disrupting chemicals distributed reactivity model black carbon

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Overexpression and characterization of a thermostable β-agarase producing neoagarotetraose from a marine isolate Microbulbifer ***1

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Acta Oceanologica Sinica 2019年第2期38卷 96-106页

作者： Yanbing Zhu He Gao Hebin li Hui Ni Zedong jiang lijun li Anfeng Xiao College of Food and Biological Engineering Jimei University Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering Research Center of Food Biotechnology of Xiamen City Key Laboratory of Systemic Utilization and In-depth Processing of Economic Seaweed Xiamen Southern Ocean Technology Center of China Department of Pharmacy Xiamen Medical College

An agarase gene containing 1 302 bp was cloned from Microbulbifer sp. AG1. It encoded a mature protein of 413 amino acids plus a 20-residue signal peptide. The recombinant enzyme without the signal peptide was expressed and purified from Escherichia coli BL21(DE3). When agarose was used as a substrate, the optimal temperature and pH for the enzyme were 60℃ and 7.5, respectively. The recombinant agarase showed excellent thermostability with 67% and 19% of residual activities after incubation at 50℃ and 60℃ for 1 h, *** SDS, the recombinant agarase had a relatively good resistance against the detected inhibitors, detergents and urea denaturant. Thin layer chromatography analysis and enzyme assay using p-nitrophenyl-α/β-Dgalactopyranoside revealed that the recombinant agarase was a β-agarase that degraded agarose into neoagarotetraose as the main end product. The enzymatic hydrolysis products with different degree of polymerization exhibited the antioxidant activities.

关键词： thermostable β-agarase neoagarotetraose Microbulbifer sp.

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A power adjustment based e ICIC algorithm for hyper-dense Het Nets considering the alteration of user association

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Science China(Information Sciences) 2015年第8期58卷 38-52页

作者： jiang Huilin TONG En li ZhiHang PHAN NhuQuan PAN ZhiWen liU Nan National Mobile Communications Research Laboratory Southeast University

This paper evaluates power adjustment based enhanced inter-cell interference coordination(e ICIC)problem in the hyper-dense Het Net under the practical serving cell selection rule where each user selects the base station with the strongest received signal power as its serving cell while the alteration of the serving cell happens during the power adjusting process. In this paper, the e ICIC problem is solved by cooperatively adjusting the transmission power of all small cells. A power adjustment method based on modified particle swarm optimization(MPSO) is proposed to tackle the NP-hard e ICIC problem caused by the alteration of the serving cell, and considering the drawbacks of MPSO, an improved MPSO is proposed for effective *** search and multi-restart process are introduced in the improved MPSO based e ICIC algorithm to guarantee the local and then global optimality, and the convergence conditions and the global optimality are proved by mathematical deduction to guide the selection of the parameters. Simulations show that, while considering the fifty-picocell case as an example, the proposed improved MPSO based e ICIC algorithm can increase the system throughput by 66.0% compared with the full power transmission, and compared with the existing schemes which do not alter the serving cells, the proposed algorithm can improve the system throughput by 32.2%. By improving MPSO, the consequent algorithm costs less iteration time to achieve higher system throughput, and it is effective and feasible to solve the e ICIC problem in the hyper-dense Het Net.

关键词： enhanced inter-cell interference coordination hyper-dense heterogeneous networks improved modified particle swarm optimization p

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Preparation of cross-linked enzyme aggregates of nitrile hydratase ES-NHT-118 from *** by macromolecular cross-linking agent

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Chinese Journal of Chemical Engineering 2017年第4期25卷 487-492页

作者： liya Zhou Haixia Mou Jing Gao li Ma Ying He Yanjun jiang School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China Hebei Provincial Key Lab of Green Chemical Technology and High Efficient Energy Saving Hebei University of TechnologyTianjin 300130China

Cross-linked enzyme aggregates(CLEAs) of nitrile hydratase(NHase) ES-NHT-118 from Escherichia coli were prepared by using ammonium sulfate as precipitating agent followed by cross-linking with dextran polyaldehyde for the first time. In this process, egg white was added as protein feeder for facilitating the formation of CLEAs. The optimal conditions of the immobilization process were determined. Michaelis constants(Km) of free NHase and NHase CLEAs were also determined. The NHase CLEAs exhibited increased stability at varied pH and temperature conditions compared to its free counterpart. When exposed to high concentrations of acrylamide, NHase CLEAs also exhibited effective catalytic activity.

关键词： nitrile linking acrylamide linker ammonium facilitating counterpart Michaelis dextran constants

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Effect of minor Sc addition on microstructure and stress corrosion cracking behavior of medium strength Al–Zn–Mg alloy

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Journal of Materials Science & Technology 2018年第7期34卷 1172-1179页

作者： Zhaoming li Haichang jiang Yunli Wang Duo Zhang Desheng Yan lijian Rong CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research. Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

Influence of Sc content on microstructure and stress corrosion cracking behavior of medium strength AI-Zn-Mg alloy have been investigated by optical microscopy, scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy and slow strain rate test. The results indicate that the addition of Sc results in the formation of the quaternary coherent AI3（Sc, Zr, Ti） dispersoids during homogenization treatment, which will inhibit the dynamic recrystallization behavior. The number density ofAl3（Sc, Zr, Ti） particles increases with the increase of Sc content, and thus the recrystallization fraction of hot-extruded alloy is reduced and the peak strength in two-stage artificial aging sample is enhanced. At the same time, the wide of precipitation free zone is reduced, and the content of Zn and Mg in grain boundary particles and precipitation free zone is increased with the increase of Sc content. In peak-aged state, the 0.06 wt% Sc added alloy shows the better stress corrosion cracking resistance than the Sc-free alloy because of the reduction of recrystallization fraction and the interrupted distribution of grain boundary precipitates along grain boundary. However, the further addition of Sc to 0.11 wt% will result in the deterioration of stress corrosion cracking resistance due to the increase of electrochemical activity of grain boundary particles and precipitation free zone as well as hydrogen embrittlement.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Aluminium alloy Al3 (Sc Zr Ti) Recrystalization Stress corrosion cracking

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Cimicifuga heracleifolia is therapeutically similar to black cohosh in relieving menopausal symptoms: evidence from pharmacological and metabolomics studies

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Chinese Journal of Natural Medicines 2019年第6期17卷 435-445页

作者： MIAO Lan-Yun CHU Thi Thanh Huyen li Ping jiang Yan li Hui-Jun State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China College of Chemical Engineering Nanjing Forestry UniversityNanjing 210037China

In the market of botanical dietary supplements, Cimicifuga heracleifolia(CH) has always been considered as an adulterated species of Cimicifuga racemosa(CR), a conventional American herb with promising benefits to counteract troubles arising from the menopause. However, the detailed comparison of their therapeutic effects is lacking. In present study, the pharmacological and metabolomics studies were comparatively conducted between CH and CR in ovariectomized(OVX) female rats. Specifically, estrogen-like, anti-hyperlipidemia and anti-osteoporosis effects were evaluated through measuring serum biochemical parameters, histopathological examination and micro computed tomography(Micro-CT) scanning. At the same time, a gas chromatography-mass spectrometry(GC-MS)-based serum metabolomics method was employed to profile the metabolite compositional changes. As a result, both CR and CH displayed anti-osteoporosis and anti-hyperlipemia on menopause syndrome. Meanwhile, their potentials in improving the OVX-induced metabolic disorders were discovered. In conclusion, these results demonstrated that CH is therapeutically similar to CR in relieving menopausal symptoms and CH could be considered as a promising alternative to CR instead of an adulterant in the market of botanical dietary supplements.

关键词： Cimicifuga heracleifolia Black cohosh Menopausal symptoms Metabolomics Substitute

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Role of the glymphatic system in ageing and diabetes mellitus impaired cognitive function

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Stroke & Vascular Neurology 2019年第2期4卷 90-92页

作者： li Zhang Michael Chopp Quan jiang Zhenggang Zhang Department of Neurology Henry Ford HospitalDetroitMichiganUSA Department of Physics Oakland UniversityRochesterMichiganUSA

Diabetes mellitus (DM) is a common metabolic disease in the middle-aged and older population, and is associated with cognitive impairment and an increased risk of developing dementia. The glymphatic system is a recently characterised brain-wide cerebrospinal fluid and interstitial fluid drainage pathway that enables the clearance of interstitial metabolic waste from the brain parenchyma. Emerging data suggest that DM and ageing impair the glymphatic system, leading to accumulation of metabolic wastes including amyloid-β within the brain parenchyma, and consequently provoking cognitive dysfunction. In this review, we concisely discuss recent findings regarding the role of the glymphatic system in DM and ageing associated cognitive impairment.

关键词： impaired mellitus system

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Spectral Characteristics of White Organic light-emitting Diodes Based on Novel Phosphorescent Sensitizer

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Chinese Journal of Chemical Physics 2008年第6期21卷 510-514页

作者： Xiao-qing Tang Jun-sheng Yu Lu li Wen Wen Ya-dong jiang State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

White organic light-emitting diodes were fabricated by using a novel phosphorescence bis（1,2-diphenyl-1H-benzoimidazole）iridium（acetylacetonate）[（pbi）2Ir（acac）] as sensitizer and a fluorescent dye of 4- （dicyanomethylene）-2-t-butyl-6-（1,1,7,7-tetramethyljulolidyl-9-enyl）-4H-pyran （DCJTB） codoped into a carbazole polymer of poly（N-vinylcarbazole）（PVK）. Through characterizing the UV-Vis absorption spectra, the photoluminescence spectra of （pbi）2Ir（acac） and DCJTB, and the electroluminescence spectral properties of the WOLEDs, the energy transfer mechanisms of the codoped polymer system were deduced. The results demonstrate that the luminescent spectra with different intensity of （pbi）2Ir（acac） and DCJTB were co-existent in the EL spectra of the blended system, which is ascribed to an incomplete energy transfer process in the EL process. The efficient Forster and Dexter energy transfer between the host and the guests enabled a strong yellow emission from （pbi）2Ir（acac） and DCJTB, where （pbi）2Ir（acac） plays an important role as a phosphorescent sensitizer for DCJTB. With the blue emitting-layer of N,N＇-diphenyl-N,N＇-bis（1- naphthyl）（1,1＇-biphenyl）-4,4＇-diamine, the codoped system device achieved white emission. The codoped system showed that its Commissions Internationale de 1＇Eclairage coordinates were more independent of the variation of bias voltage than those of phosphorescent doped PVK systems.

关键词： White organic light-emitting diode Phosphorescent sensitizer Spectrum analysis

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Cold and hot tumors:from molecular mechanisms to targeted therapy

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Signal Transduction and Targeted Therapy 2024年第11期9卷 5079-5143页

作者： Bo Wu Bo Zhang Bowen li Haoqi Wu Meixi jiang Department of Neurology The Fourth Affiliated HospitalChina Medical UniversityShenyangChina Department of Youth League Committee The Fourth Affiliated HospitalChina Medical UniversityShenyangChina Department of Pancreatic and Gastrointestinal Surgery Ningbo No.2 HospitalNingboChina Department of Gynaecology and Obstetrics The Second Hospital of Dalian Medical UniversityDalianChina

Immunotherapy has made significant strides in cancer treatment,particularly through immune checkpoint blockade(ICB),which has shown notable clinical benefits across various tumor *** the transformative impact of ICB treatment in cancer therapy,only a minority of patients exhibit a positive response to *** patients with solid tumors,those who respond well to ICB treatment typically demonstrate an active immune profile referred to as the“hot”(immune-inflamed)*** the other hand,non-responsive patients may exhibit a distinct“cold”(immune-desert)phenotype,differing from the features of“hot”***,there is a more nuanced“excluded”immune phenotype,positioned between the“cold”and“hot”categories,known as the immune“excluded”*** differentiation between“cold”and“hot”tumors,and understanding tumor intrinsic factors,immune characteristics,TME,and external factors are critical for predicting tumor response and treatment *** is widely accepted that ICB therapy exerts a more profound effect on“hot”tumors,with limited efficacy against“cold”or“altered”tumors,necessitating combinations with other therapeutic modalities to enhance immune cell infiltration into tumor tissue and convert“cold”or“altered”tumors into“hot”***,aligning with the traits of“cold”and“hot”tumors,this review systematically delineates the respective immune characteristics,influencing factors,and extensively discusses varied treatment approaches and drug targets based on“cold”and“hot”tumors to assess clinical efficacy.

关键词： tumors treatment spite

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