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Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： jun zha Huijie zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

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Residual field suppression for magnetocardiography measurement inside a thin magnetically shielded room using bi-planar coil

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Chinese Physics B 2022年第7期31卷 229-234页

作者： Kang Yang Hong-Wei zhang Qian-Nian zhang jun-jun zha Deng-Chao Huang College of Electrical Engineering Anhui Polytechnic UniversityWuhu 241000China Key Laboratory of Advanced Perception and Intelligent Control of High-end Equipment Ministry of EducationAnhui Polytechnic UniversityWuhu 241000China

For a magnetocardiography(MCG)system inside a magnetically shielded room(MSR),the residual field should be further suppressed to obtain high-quality MCG *** this paper,a compensation system has been developed based on the bi-planar coil and the proportional-integral-derivative(PID)*** bi-planar coil,derived from the target-field theory and the Tikhonov regularization method,is utilized to generate magnetic field with high uniformity in the predefined target *** the PID controller is introduced to provide dynamic compensation current for the coil,according to the residual field change monitored by a reference SQUID *** measurement results show that the noise suppression ratio(NSR)can reach above 20 dB in the low-frequency range from 0.1 Hz to 50 *** DC component and the fluctuation of the residual field in time-domain can be respectively suppressed to 0 p T and 4 p T,indicating that this proposed compensation method is useful for the MCG measurement.

关键词： SQUID magnetocardiography bi-planar coil active compensation

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Atomic tailoring-induced deficiency in tungsten oxides for high-performance energy-related devices

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Tungsten 2024年第2期6卷 269-277页

作者： Jing-Huang Lin Yao-Tian Yan jun-Lei Qi Chen-Yang zha Institute of Applied Physics and Materials Engineering Zhuhai UM Science and Technology Research InstituteUniversity of MacaoTaipaMacao SAR 999078China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Jiangmen Laboratory of Carbon Science and Technology Hong Kong University of Science and Technology(Guangzhou)Jiangmen 529199China Key Laboratory of Flexible Electronics School of Flexible Electronics(Future Technologies)Institute of Advanced MaterialsNanjing Tech UniversityNanjing 211816China

Nowadays,tungsten oxides,as a typical transition metal oxide,are widely and intensively investigated owing to their excellent material properties and device *** oxygen defi ciency in tungsten oxides is typically the key to enhance their performances for a variety of critical technological *** a gradual increase of oxygen defi ciency,various non-stoichiometric tungsten oxides can be formed by re-adjustment of the atomic arrangement,which exhibits superior performances than their traditional stoichiometric *** review mainly focuses on the recent advances in oxygen-defi cient tungsten oxides from the point of atomic structures,including the forming mechanism of non-stoichiometric tungsten oxides and the superiority of these oxygen-defi cient tungsten oxides in energy-related ***,the challenge and perspective of oxygen-defi cient tungsten oxides are also discussed.

关键词： Oxygen defi ciency Tungsten oxide Atomic structures Catalyst Storage

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Risk factors for postpartum posttraumatic stress disorder after emergency admission

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World Journal of Emergency Medicine 2024年第2期15卷 121-125页

作者： Fengxia Du jun zha Yan Li Lichao Fang Shuyu Xia Youjia Yu Department of Obstetrics Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Anesthesiology the Second Affiliated Hospital of Wannan Medical CollegeWuhu 241000China Department of Anesthesiology Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Emergency and Intensive Care Unit Suzhou Xiangcheng People’s HospitalSuzhou 215131China

BACKGROUND:Postpartum posttraumatic stress disorder(PTSD)can occur in women who give birth after emergency *** identification of risk factors for this condition is crucial for developing effective preventive *** retrospective study aimed to explore the incidence and risk factors for postpartum PTSD in women who give birth after emergency ***:Medical records of women who gave birth after emergency admission were collected between March 2021 and April *** patients’general conditions and perinatal clinical indicators were *** puerperae were divided into PTSD group and control group based on symptom occurrence at six weeks *** logistic regression analysis was performed to identify risk ***:A total of 276 puerperae were included,with a PTSD incidence of 20.3% at six weeks *** logistic regression analysis identified emergency cesarean section(odds ratio[OR]=2.102;95%confidence interval[CI]:1.114-3.966,P=0.022),admission to the emergency department after midnight(12:00 AM)(OR=2.245;95%CI:1.170-4.305,P<0.001),and cervical dilation(OR=3.203;95%CI:1.670–6.141,P=0.039)as independent risk factors for postpartum *** pump use(OR=0.500;95%CI:0.259–0.966,P=0.015)was found to be a protective factor against postpartum ***:Emergency cesarean section,admission to the emergency department after midnight,and cervical dilation were identified as independent risk factors for postpartum PTSD,while analgesic pump use was a protective *** findings provide insights for developing more effective preventive measures for women who give birth after emergency admission.

关键词： Risk factors Posttraumatic stress disorder Emergency Delivery

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Intramolecular Hydrogen Bond Improved Durability and Kinetics for Zinc‑Organic Batteries

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Nano-Micro Letters 2024年第3期16卷 138-148页

作者： Tianjiang Sun jun Pan Weijia zhang Xiaodi Jiang Min Cheng Zhengtai zha Hong Jin Fan zhanliang Tao Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityHaihe Laboratory of Sustainable Chemical TransformationsTianjin 300071People’s Republic of China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092People’s Republic of China

Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic ***,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)*** intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in *** situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current ***,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular *** work provides an efficient approach toward insoluble organic electrode materials.

关键词： Zn-organic batteries H-PNADBQ polymer Intramolecular hydrogen bond Reduced solubility Improvedπ-conjugated level

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A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai Lin Hao zha Jia-Ru Shi Qiang Gao Fang-jun Hu Qing-Zhu Li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

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Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei zhang Yufan Li Yuchao Li Zhonggui Sun Hanxue Zhu Lujia Yang Yanhu zhan Yankai Li Shi Wang jun-Wei zha School of Mathematical Sciences Liaocheng University School of Materials Science and Engineering Liaocheng University State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications School of Chemistry and Biological Engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Breakdown strength Composites Dielectric constant Sandwich structure Thermal conductivity

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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao Wang Zhong-jian zha Hai-jun Bai Jiang Wang Development and Research Center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Institute of Geological Surveying and Mapping Technology of Anhui Province Hefei 230022China Third Geological Brigade of Hebei Bureau of Geology and Mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering

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Elevated peripheral levels of receptor-interacting protein kinase 1(RIPK1)and IL-8 as biomarkers of human amyotrophic lateral sclerosis

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Signal Transduction and Targeted Therapy 2024年第1期9卷 271-278页

作者： jun Wei Min Li Zhi Ye Xinqian Hu Xiaoyan He Jia Wang Gaofeng Chen Chengyu Zou Daichao Xu Hongbing zhang junying Yuan Yunhong zha Institute of Neural Regeneration and Repair and Department of Neurology The First College of Clinical Medical ScienceYichang Central HospitalCollege of Basic Medical ScienceChina Three Gorges UniversityHubei Province Clinical Medical Research Center for Rare Diseases of Nervous SystemYichang 443000China Interdisciplinary Research Center on Biology and Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai Key Laboratory of Aging StudiesShanghai 201210China State Key Laboratory of Common Mechanism Research for Major Diseases Haihe Laboratory of Cell EcosystemDepartment of PhysiologyInstitute of Basic Medical Sciences and School of Basic MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Amyotrophic lateral sclerosis(ALS)is a devastating fatal neurodegenerative disease with no ***-interacting protein kinase 1(RIPK1)has been proposed to mediate pathogenesis of *** has been identified as an old drug that can also inhibit RIPK1 *** conducted a drug-repurposing biomarker study of primidone as a RIPK1 inhibitor using SOD1G93A mice and ALS ***1G93A mice treated with primidone showed significant delay of symptomatic onset and improved motor ***-hundred-sixty-two ALS participants dosed daily with primidone(62.5 mg)completed 24-week follow-up.A significant reduction was showed in serum levels of RIPK1 and IL-8,which were significantly higher in ALS patients than that of healthy controls(P<0.0001).Serum RIPK1 levels were correlated positively with the severity of bulbar symptoms(P<0.05).Our study suggests that serum levels of RIPK1 and IL-8 in peripheral can be used as clinical biomarkers for the activation of RIPK1 in central nervous system in human ALS *** primidone may provide a promising therapeutic strategy for *** effect of primidone for the treatment of other inflammatory diseases may also be considered,since the activation of RIPK1 has been implicated in mediating a variety of inflammatory diseases including COVID-19-associated cytokine release syndrome(CRS).(ChiCTR2200060149).

关键词： RIPK1 diseases Serum

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Acupuncture for cervical dystonia associated with anxiety and depression: A case report

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World Journal of Clinical Cases 2024年第1期12卷 204-209页

作者： Ya-Ting zhang Jin-Jing zhang Bi-Xiang zha Yin-Qiu Fan Yuan-Bo Xu jun Yang Qing-Ping zhang The First School of Clinical Medicine Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina Acupuncture and Rehabilitation Department First Affiliated Hospital of Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina College of Acupuncture and Tuina Anhui University of Chinese MedicineHefei 230031Anhui ProvinceChina

BACKGROUND Cervical dystonia(CD)is a type of muscle tone disorder that usually occurs in the neck *** to the intermittent or continuous involuntary contraction of the neck muscles,the head and neck are twisted and skewed and some postural abnormalities ***-term abnormal posture or pain can cause negative emotions in patients,which can affect their quality of *** SUMMARY This case report included a 37-year-old woman who was diagnosed with CD associated with anxiety and depression;the accompanying symptoms were head and neck tilt of approximately 90°to the right and mental *** two courses of acupuncture treatment,the patient’s head and neck can be maintained in a normal position,and the negative emotions can be *** This case indicates that acupuncture can effectively improve CD and the emotional state and quality of life of patients,making it an effective alternative treatment for the condition.

关键词： Cervical dystonia Anxiety and depression Neurological disease Acupuncture Case report

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