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Research Review of Principles and Methods for Ultrasonic Measurement of Axial Stress in Bolts

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 44-59页

作者： Qinxue Pan Ruipeng Pan Chang Shao Meile Chang xiaoyu xu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of TechnologyBeijing 100081China

Bolts are important fasteners indispensable in the manufacturing field for their advantages, which include convenient assembly and disassembly, easy maintenance, refastenability to prevent looseness, and the avoidance of a phase change in the connected material composition. The precise control of the tightening force in bolts is closely related to the safety and reliability of the connected equipment or structure. Although there are many methods for estimating the tightening force applied to a bolt during assembly, poor accuracy in controlling the preload during the tightening process and a lack of monitoring to determine the residual axial force in service remain issues in evaluating the safety of bolted assemblies. As a nondestructive testing technology, ultrasonic measurement can be applied to successfully address these issues. In order to help researchers understand the theoretical basis and technological development in this field and to equip them to conduct further in-depth research, in this review, the basic knowledge describing the state of stress and deformation of bolts, as well as conventional testing methods are summarized and analyzed. Then, through a review of recent research of the ultrasonic measurement of the axial stress in bolts, the influence of the e ective stressed length and temperature are analyzed and proposed methods of calibration and compensation are reviewed. In order to avoid coupling errors caused by traditional piezoelectric transducers, two newly proposed ultrasonic coupling technologies, the electromagnetic acoustic transducer(EMAT) and the permanent mounted transducer system(PMTS), are reviewed. Finally, the new direction of research of the detection of residual axial stress in in-service bolts that have been assembled to yield is discussed.

关键词： Bolted connections Axial stress Ultrasonic waves Influencing factors Coupling techniques

Gd–La codoped TiO2 nanoparticles as solar photocatalysts

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Progress in Natural Science:Materials International 2015年第1期25卷 6-11页

作者： Meng Wang xiaoyu xu Lin Lin Dannong He School of Materials Science and Engineering Shanghai Jiao Tong University National Engineering Research Center for Nanotechnology

Gd–La codoped Ti O2 nanoparticles with diameter of 10 nm were successfully synthesized via a sol–gel method. The photocatalytic activity of the Gd–La codoped Ti O2 nanoparticles evaluated by photodegrading methyl orange was significantly enhanced compared to that of undoped or Gd or La mono-doped Ti O2. Ti4+tmay substitute for La3+tand Gd3+tin the lattices of rare earth oxides to create abundant oxygen vacancies and surface defects for electron trapping and dye adsorption, accelerating the separation of photogenerated electron–hole pairs and methyl orange photodegradation. It is believed that the formation of an excitation energy level below the conduction band of Ti O2 from the binding of electrons and oxygen vacancies decreases the excitation energy of Gd–La codoped Ti O2, resulting in versatile solar photocatalysts. The results suggest that Gd–La codoped Ti O2 nanoparticles are promising for future solar photocatalysts.

关键词： Photocatalyst Titaninm dioxide Semiconductor Photodegradation Nanotechnology

Moving target defense of routing randomization with deep reinforcement learning against eavesdropping attack

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Digital Communications and Networks 2022年第3期8卷 373-387页

作者： xiaoyu xu Hao Hu Yuling Liu Jinglei Tan Hongqi Zhang Haotian Song Academy of People’s Armed Police Beijing100012China PLA SSF Information Engineering University Zhengzhou450001China Institute of Information Engineering Chinese Academy of SciencesBeijing100093China School of Cyber Security University of Chinese Academy of SciencesBeijing101408China

Eavesdropping attacks have become one of the most common attacks on networks because of their easy implementation. Eavesdropping attacks not only lead to transmission data leakage but also develop into other more harmful attacks. Routing randomization is a relevant research direction for moving target defense, which has been proven to be an effective method to resist eavesdropping attacks. To counter eavesdropping attacks, in this study, we analyzed the existing routing randomization methods and found that their security and usability need to be further improved. According to the characteristics of eavesdropping attacks, which are “latent and transferable”, a routing randomization defense method based on deep reinforcement learning is proposed. The proposed method realizes routing randomization on packet-level granularity using programmable switches. To improve the security and quality of service of legitimate services in networks, we use the deep deterministic policy gradient to generate random routing schemes with support from powerful network state awareness. In-band network telemetry provides real-time, accurate, and comprehensive network state awareness for the proposed method. Various experiments show that compared with other typical routing randomization defense methods, the proposed method has obvious advantages in security and usability against eavesdropping attacks.

关键词： Routing randomization Moving target defense Deep reinforcement learning Deep deterministic policy gradient

Analysis of morphological characteristics of gravels based on digital image processing technology and self-organizing map

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Journal of Arid Land 2023年第3期15卷 310-326页

作者： xu Tao YU Huan QIU Xia KONG Bo XIANG Qing xu xiaoyu FU Hao College of Earth Science Chengdu University of TechnologyChengdu 610059China Beijing SuperMap Software Co. Ltd.Beijing 100015China Sichuan Real Estate Registration Center Chengdu 610014China Chengdu Institute of Mountain Land and Disasters Chinese Academy of SciencesChengdu 610041China School of Earth Systems and Sustainability Southern Illinois University CarbondaleCarbondaleIL 62901United States of America Environmental Resources and Policy Southern Illinois University CarbondaleCarbondaleIL 62901United States of America Sichuan Institute of Land and Space Ecological Restoration and Geohazard Prevention Chengdu 610081China

A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and ***,traditional methods for studying gravels are low-efficiency and have many *** study researched the spatial distribution and cluster characteristics of gravels based on digital image processing technology combined with a self-organizing map(SOM)and multivariate statistical methods in the grassland of northern Tibetan ***,the correlation of morphological parameters of gravels between different cluster groups and the environmental factors affecting gravel distribution were *** results showed that the morphological characteristics of gravels in northern region(cluster C)and southern region(cluster B)of the Tibetan Plateau were similar,with a low gravel coverage,small gravel diameter,and elongated *** regions were mainly distributed in high mountainous areas with large topographic *** central region(cluster A)has high coverage of gravels with a larger diameter,mainly distributed in high-altitude plains with smaller *** component analysis(PCA)results showed that the gravel distribution of cluster A may be mainly affected by vegetation,while those in clusters B and C could be mainly affected by topography,climate,and *** study confirmed that the combination of digital image processing technology and SOM could effectively analyzed the spatial distribution characteristics of gravels,providing a new mode for gravel research.

关键词： self-organizing map digital image processing morphological characteristics multivariate statistical method environmental monitoring

Metal-organic framework(MOF)-based biomaterials in bone tissue engineering

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Engineered Regeneration 2021年第1期2卷 105-108页

作者： Chang Liu xiaoyu xu Wenguo Cui Hongbo Zhang Pharmaceutical Sciences Laboratory Faculty of Science and EngineeringÅbo Akademi UniversityTurku 20520Finland Turku Bioscience Centre University of Turku andÅbo Akademi UniversityTurku 20520Finland ENT Institute and Department of Otorhinolaryngology Eye&ENT HospitalState Key Laboratory of Medical NeurobiologyInstitutes of Biomedical SciencesFudan UniversityShanghai 200031China Department of Orthopaedics Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint DiseasesShanghai Institute of Traumatology and OrthopaedicsRuijin HospitalShanghai Jiao Tong University School of Medicine197 Ruijin 2nd RoadShanghai 200025China

Bone defects caused by congenital diseases,trauma,infection,tumors,or other factors are common orthopedic diseases,which affect the normal movement of patients significantly.[1]Clinical intervention is still required to achieve the complete healing and functional *** that,the autologous or allogeneic bone grafts are the present gold standard treatment for large or severe bone damage,with about 2.2 million bone grafting operations being performed annually globally.

关键词： healing diseases Clinical

Probiotic Medilac-S^(█) for the induction of clinical remission in a Chinese population with ulcerative colitis: A systematic review and meta-analysis

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World Journal of Clinical Cases 2018年第15期6卷 961-984页

作者： Ghania Sohail xiaoyu xu Mary C Christman Thomas A Tompkins Lallemand Health Solutions Inc. MCC Statistical Consulting

AIM To assess the effects of probiotic Medilac-S~ as adjunctive therapy for the induction of remission of ulcerative colitis(UC) in a Chinese population through a systematic review and meta-analysis. METHODS A systematic literature search was conducted to find randomized, controlled trials in a Chinese population with at least two study arms-a control arm which receives a conventional, oral aminosalicylate drug, and a treatment arm, which administers the same conventional drug in conjunction with the probiotic Medilac-S~ per os. Both English and Chinese databases were searched, including Pub Med, EMBASE, Google Scholar, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Search, and study data was extracted onto standardized abstraction sheets. Meta-analyses were conducted for primary and secondary outcomes of interest using a fixed or random effects model. The primary outcome was the induction of clinical remission and the secondary outcomes included changes in Sutherland index, endoscopic and histological scores, proportion of reported clinical symptoms and adverse events(AEs). For outcomes with sufficient data, the type of conventional drug therapy was also assessed to determine if the effects of combination therapy with Medilac-S~ was influenced by drug type. All tests were conducted using a type Ⅰ error rate of 0.05 and all confidence intervals(CI) were based on a 95% confidence level. Review protocol was uploaded to PROSPERO(CRD42018085658 upon completion).RESULTS Fifty-three clinical trials with a total of 3984 participants were identified and included in the review. Medilac-S~ adjunctive therapy significantly improved induction of clinical remission(RR = 1.21; 95%CI: 1.18-1.24; P < 0.0001) with the estimated likelihood of effective treatment, on average, 21% higher for those consuming the probiotic. Sutherland index scores showed the control mean was on average 3.10(CI: 2.41-3.78; P = 0.0428) units greater than the treatment mean, thereby de

关键词： Clinical remission Systematic review Meta-analysis Mesalazine Sulfasalazine Ulcerative colitis Medilac-S^(█)

Excitation orthogonalized upconversion nanoprobe for instant visual detection of trinitrotoluene

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Nano Research 2023年第1期16卷 1491-1499页

作者： xu Li xu Zhao xiaoyu xu Yang Lu Jiahang Wu Fangmeng Liu xu Yan Peng Sun Chenguang Wang Xianggui Kong Xiaomin Liu Geyu Lu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China Department of Public Security of Jilin Province Changchun 130051China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and physicsChinese Academy of ScienceChangchun 130033China

Excitation-emission orthogonalized luminescent upconversion nanoparticles(OUCNPs),which can respond to changes in external stimuli accordingly,show great promise in many intelligent ***,the construction of such materials mostly relies on the selective absorption of Nd3+and Yb3+at different wavelengths and the long-range energy migration between the layers,resulting in complex structures and limited orthogonal luminescence ***,we developed a relatively simple structure of OUCNPs(β-NaErF4@NaLuF4@NaYF4:20%Yb,2%Er@NaLuF4),where the fluorescence emission switches from red to green when the excitation wavelength is shifted from 808 to 980 *** structure exhibits high-quality,independent,and non-interfering orthogonal luminescence properties without Nd3+sensitization and long-range energy *** a proof of concept,we demonstrate the application of the designed OUCNPs in *** also prepared OUCNPs@PEI(PEI=polyethylenimine)self-referencing fluorescent probes to enable quantitative analysis of trinitrotoluene(TNT)in solution with a detection limit of 3.04μ*** probes can be made into test strips for portable on-site visual detection of TNT,and can also be used to image latent fingerprints and detect explosive residues in fingerprints *** concept proposed in this work can be extended to the visual detection of a larger range of organic and biological molecules,and is highly promising for practical applications.

关键词： orthogonal luminescence NaErF4 core/multi-shell structure anti-counterfeiting trinitrotoluene(TNT)detection

Gp130-dependent STAT3 activation in M-CSF-derived macrophages exaggerates tumor progression

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Genes & Diseases 2024年第3期11卷 51-54页

作者： Yuting xu xiaoyu xu Qianyue Zhang Peizhe Lu Chongjun Xiang Lei Zhang Chunhua Lin Qiaoling Song Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdaoShandong 266003China College of Marine Life Sciences Ocean University of ChinaQingdaoShandong 266071China Department of Neuroscience University of MichiganAnn ArborM/48103USA Department of Urology The Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantaiShandong 264000China Research Center of Traditional Chinese Medicine and Clinical Pharmacy Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao UniversityJinanShandong 250014China Innovation Platform of Marine Drug Screening&Evaluation Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266100China

Interleukin-6(IL-6)is a common pluripotent cytokine that is highly expressed in the tumor *** IL-6/JAK/STAT3 signaling directly promotes tumor progression,severely hampering antitumor ***,the richest innate immune cel... 详细信息

关键词： STAT3 tumor Interleukin

Bone-seeking nanoplatform co-delivering cisplatin and zoledronate for synergistic therapy of breast cancer bone metastasis and bone resorption

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Acta Pharmaceutica Sinica B 2020年第12期10卷 2384-2403页

作者： Yanjuan Huang Zhanghong Xiao Zilin Guan Zishan Zeng Yifeng Shen xiaoyu xu Chunshun Zhao School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China

The"vicious cycle"established between tumor growth and osteolysis aggravates the process of breast cancer bone metastasis,leading to life-threatening skeletal-related events that severely reduce survival and quality of *** effectively interrupt the"vicious cycle",innovative therapeutic strategies that not only reduce osteolysis but also relieve tumor burden are urgently ***,a bone-seeking moiety,alendronate(ALN),functionalized coordination polymer nanoparticles(DZ@ALN)co-delivering cisplatin prodrug(DSP)and antiresorptive agent zoledronate(ZOL)via Zn2+crosslinking for combination therapy was *** versatile DZ@ALN with a diameter of about 40 nm can cross the fissure in the bone marrow sinus capillaries,and possesses an excellent bone-seeking ability both in vitro and in ***,DZ@ALN could synergistically inhibit the proliferation of cancer cells,suppress the formation of osteoclast-like cells and induce the apoptosis of osteoclasts in ***,it could preferentially accumulate in bone affected site,remarkably inhibit the proliferation of tumor cells,relieving bone pain,and significantly inhibit the activation of osteoclasts,protecting the bone from destruction in vivo,eventually leading to the breakdown of"vicious cycle"without inducing obvious systemic *** innovative nanoagent combines chemotherapy and osteolysis inhibition,exhibiting an inspiring strategy for effective treatment of bone metastasis.

关键词： Bone metastasis Bone targeting Osteolysis Zoledronate Cisplatin