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Thermal Error Compensation of the Wear-Depth Real-Time Detecting of Self-Lubricating Spherical Plain Bearings

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 35-47页

作者： Zhan-Qi Hu Wei li Yu-lin Yang Bing-li Fan hai-li zhou Aviation Key Laboratory of Science and Technology on Generic Technology of Aviation Self-Lubricating Spherical Plain Bearing Yanshan University

The spherical plain bearing test bench is a necessary detecting equipment in the research process of self?lubricating spherical plain bearings. The varying environmental temperatures cause the thermal deformation of the wear?depth detecting system of bearing test benches and then a ect the accuracy of the wear?depth detecting data. However, few researches about the spherical plain bearing test benches can be found with the implementation of the detect?ing error compensation. Based on the self?made modular spherical plain bearing test bench, two main causes of ther?mal errors, the friction heat of bearings and the environmental temperature variation, are analysed. The thermal errors caused by the friction heat of bearings are calculated, and the thermal deformation of the wear?depth detecting sys?tem caused by the varying environmental temperatures is detected. In view of the above results, the environmental temperature variation is the main cause of the two error factors. When the environmental temperatures rise is 10.3 °C, the thermal deformation is approximately 0.01 mm. In addition, the comprehensive compensating model of the thermal error of the wear?depth detecting system is built by multiple linear regression(MLR) and time series analysis. Compared with the detecting data of the thermal errors, the comprehensive compensating model has higher fitting precision, and the maximum residual is only 1 μm. A comprehensive compensating model of the thermal error of the wear?depth detecting system is proposed, which provides a theoretical basis for the improvement of the real?time wear?depth detecting precision of the spherical plain bearing test bench.

关键词： Self?lubricating spherical plain bearing Wear depth Bearing test bench Thermal error Error compensation

Steroidal saponins from the roots of Asparagus cochinchinensis

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Chinese Journal of Natural Medicines 2014年第3期12卷 213-217页

作者： ZHU Guo-Lei HAO Qian li Rong-Tao li hai-zhou Faculty of life Science and Technology Kunming University of Science and Technology

AIM： To study the chemical constituents of the roots of Asparagus cochinchinensis （Asparagaceae）. METHOD： The compounds were isolated with Diaion HP20, silica gel, and ODS chromatography, and their structures were de- termined on the basis of chemical methods, HR-ESI-MS, and 1 D- and 2D-NMR techniques. RESULTS： Seven compounds were isolated from the n-butanol fraction of the roots of A. cochinchinensis, and their structures were elucidated as （25S）-26-O-β-D-glucopyranosyl-5β-furostan-3β, 22a, 26-triol-12-one-3-O-β-D-glucopyranoside （1）, （25S）-26- O-β-D-glucopyranosyl-22a-methoxy-5β-furostan-3p, 26-diol-12-one-3-O-β-D-glucopyranoside （2）, （25S）-26-O-β-D-glucopyra- nosyl-5β-furostan-3β, 22a, 26-triol （3）, （25S）-26-O-β-D-glucopyranosyl-5β-furstan-3β, 22a, 26-triol-3-O-β-D-glucopyranoside （4）, （25S）-26-O-β-D-glucopyranosyl-5β-furostan-3β, 22a, 26-triol-3-O-a-L-rhamnopyranosyl-（1, 4）-β-D-glucopyranoside （5）, （25S）- 5β-spirostan-3fl-ol-3-O-a-L-rhamnopyranoside （6）, and （25S）-5β-spirostan-3β-ol-3-O-β-D-glucopyranoside （7）. CONCLUSION： Compounds 1 and 2 were two new furostanol saponins.

关键词： Asparagus cochinchinensis Asparagaceae Steroidal saponins

Multiple sub-array beamspace CAATI algorithm for multi-beam bathymetry system

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Journal of Marine Science and Application 2007年第1期6卷 47-52页

作者： li Zi-sheng li hai-sen zhou Tian YUAN Yan-yi College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

This paper extends CAATI （Computed Angle-of-Arrival Transient Imaging） technique of Multi-angle Swath Bathymetry Sidesean Sonar （MSBSS） into Multi-Beam Bathymetry Sonar （MBBS） and presents a new Multiple Sub-array Beamspaee - CAATI （MSB-CAATI） algorithm. The method not only can achieve high resolution seafloor mapping in the whole wide swath, but also can work well in complex acoustic environments or geometries. Simulation results and processing results of sea-experiment data prove the validity and superiority of the algorithm.

关键词： MSB-CAATI swath bathymetry high resolution multi-beam

Combined Acupuncture and Bloodletting on Chize(LU 5)and Weizhong(BL 40)for Chronic Eczema

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Journal of Acupuncture and Tuina Science 2013年第5期11卷 269-271页

作者： Xie Kai li hai-zhou Han Chou-ping Acupuncture Department Zhenhai Lianhua Hospital of Ningbo Ningbo Tianyi Vocational and Technical College

Objective： To observe the clinical effect of combined acupuncture with bloodletting on Chize （LU 5） and Weizhong （BL 9） for chronic eczema. Methods： A total of 40 cases were randomly allocated into an observation group and a control group, 20 in each. Cases in the observation group were treated with acupuncture plus bloodletting on Chize （LU 5） and Weizhong （BL 9）, whereas cases in the control group were treated with acupuncture alone. The acupuncture was conducted once a day, bloodletting twice a week. The therapeutic efficacy was statistically analyzed after one month of consecutive treatment. Results： The recovery and total effective rates in the observation group were significantly higher than that in the control group （P〈O.05）. Conclusion： Combined acupuncture and bloodletting on Chize （LU 5） and Weizhong （BL 40） could obtain a better effect than acupuncture alone.

关键词： Acupuncture Therapy Bloodletting Therapy Eczema Points, Chize(LU 5) Points, Weizhong (BL 40)

Ultrafast investigation of room temperature valley polarization in“optical bilayer”WS_(2)

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Science China(Technological Sciences) 2024年第1期67卷 91-97页

作者： ZHAO LeYi WANG hai liU TianYu li FangFei zhou Qiang WANG haiYu Synergetic Extreme Condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Monolayer transition metal dichalcogenides(TMDCs)have become a promising platform in valleytronics due to possessing the regulatable valley degrees of ***,as a result of the rapid intervalley scattering,it is difficult to measure the PL valley polarization of monolayer TMDCs at room temperature,which limits their application in valleytronics ***,we report a room temperature photoluminescence(PL)valley polarization up to 3.73%in an“optical bilayer”WS_(2)formed by transferring monolayer WS_(2)onto flat Ag ***,in the transient absorption(TA)measurements,a remarkably long valley depolarization lifetime is ***,we demonstrate the valley properties of such“optical bilayer”WS_(2)resemble actual bilayer WS_(2),in which the robust valley polarization can be attributed to the phonons depletion effect and the blocked interlayer hopping *** peculiar valley features in“optical bilayer”WS_(2)provide a particularly simple method to enhance valley control at room temperature.

关键词： valleytronics optical bilayer transient absorption tungsten disulfide

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： hai-Jun li Ying-Quan Peng Wei Chao Yu-Feng zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Effect of Needle-retaining Time on Therapeutic Efficacy for Post-stroke Hemiplegia

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Journal of Acupuncture and Tuina Science 2013年第4期11卷 222-225页

作者： li hai-zhou Xie Kai zhou li-feng Fu Qing-lan Zheng Pei-hong Han Chou-ping Rehabilitative Care Technique Teaching and Research Room Ningbo Tianyi Polytechnic lianhua Hospital Zhenhai District

Objective： To observe the effect of needle-retaining time in scalp acupuncture on therapeutic efficacy for post-stroke hemiplegia. Methods： A total of 82 cases who met the inclusion criteria were randomly allocated into a control group （22 cases）, a short-time needle- retaining group （30 cases） and a long-time needle-retaining group （30 cases）. Conventional Bobath therapy was employed in the control group while the scalp acupuncture was combined in the short-time （0.5 h） needle-retaining group and long-time （24 h） needle-retaining group. Then functional assessments were made 1 month and 3 months after treatment using FugI-Meyer motor scale {FMMS）, FugI-Meyer assessment of balance （FMA-B） and modified Barthel index （MBI） score. Results： Cases in the long-time needle-retaining group obtained better effects in motor function of the limbs and activities of daily living （ADL） than the other two groups （P〈0.05）. In addition, there was no statistical significance between the short-time needle-retaining group and the control group （P〉0.05）. Conclusion： The needle-retaining time in scalp acupuncture is substantially associated with the effect for post-stroke hemiplegia and long-time needle-retaining is more advisable.

关键词： Acupuncture Therapy Scalp acupuncture Stroke Complications Hemiplegia Rehabilitation

Consensus on glycemic management for patients with coronary heart disease and type 2 diabetes

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Journal of Geriatric Cardiology 2024年第7期21卷 689-702页

作者： li-Nong JI Yun-Dai CHEN Jing liU Xiang-hai zhou Cardiovascular Subcommittee of Chinese International Exchange and Promotion Association for Medical and Healthcare Peking University People's Hospital Chinese PLA General Hospital

The prevalence of patients with coronary heart disease(CHD)and diabetes mellitus is notably high,posing sig-nificant residual cardiovascular risks even after routine interventions such as antihypertensive,lipid-lowering,and antithrombot-ic *** studies have demonstrated that certain glucose-lowering medications confer cardiovascular benefits for pa-tients with type 2 ***,a survey indicates that cardiologists may not be fully acquainted with the optimal screen-ing timing,indicators,and diagnostic criteria for type 2 diabetes,and there is insufficient awareness and a low rate of prescrip-tion of novel glucose-lowering medications with proven cardiovascular efficacy,such as glucagon-like peptide-1 receptor agon-ists(GLP-1 RAs)and sodium-glucose co-transporter-2 inhibitors(SGLT-2i).In this context,based on domestic and international guidelines or consensus and the latest evidence-based evidence,this consensus aims to standardize the glycemic management for patients with acute coronary syndrome,chronic coronary syndrome,and perioperative management for percutaneous coronary *** highlights the key points of screening and diagnosis of type 2 diabetes,and the comprehensive management of cardiovascular risk in patients with *** consensus elaborates on the principles and algorithms of glycemic management for CHD patients,without involving acute complications of diabetes,clarifies the clinical practice of glucose-lowering medications with cardiovascular benefits,and promotes the standardized use of these medications in cardiovascular and other related spe-cialty ***,it addresses the glucose-lowering treatment to comprehensively reduce cardiovascular risks.

关键词： coronary patients routine

Propylene epoxidation coupled with furfural oxidation over Pt(Ⅱ?) TPP porphyrin with molecular oxygen

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Green Chemical Engineering 2024年第4期5卷 519-525页

作者： Hong-Qi li hai-Yang Yu Yang li Xiao-Qi He Xian-Tai zhou Huizhou Research Institute Sun Yat-sen University School of Chemical Engineering and Technology Sun Yat-sen University

The development of green route for preparing propylene oxide (PO) with molecular oxygen is of significance both in academic and industrial. In this work, propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin (Pt (II)TPP) has been developed. Propylene conversion and PO selectivity reached up to 56%and 83%, respectively. Meanwhile, furfural was almost completely converted to furoic *** on operando characterizations and electron paramagnetic resonance (EPR) tests, a mechanism involved high-valent Pt species was proposed. This work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry.

关键词： Propylene Epoxidation Molecular oxygen Furfural Platinum porphyrins