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Output Waveform Analysis of an Electro-hydraulic Vibrator Controlled by the Multiple Valves

Chinese Journal of Mechanical Engineering 2014年第1期27卷 186-197页

作者： REN Yan RUAN jian jia Wen'ang College of Mechanical & Electrical Engineering Wenzhou University Key Laboratory of Special Purpose Equipment and Advanced Machining Technology Ministry of Education & Zhejiang Province Zhejiang University of Technology

The existing research of the electro-hydraulic vibrator mainly focuses on system stability, working frequency width and output waveform distortion. However, this high frequency performance of the electro-hydraulic vibrator is difficult to be improved greatly due to fast insufficiently frequency response of the servo valve itself and limited compensation capability of the control structure in the vibrator system. In this paper, to realize high frequency vibration, an improved two-dimensional valve （here within defined as a 2D valve） as a main control component is adopted to the parallel connection with a servo valve to control the electro-hydraulic vibrator, Because the output waveforms of this electro-hydraulic vibrator are incapable to be verified through timely feedback as in the conventional electro-hydraulic servo system, the analysis to the output waveform becomes crucial to the design and control of the electro-hydraulic vibrator. The mathematical models of hydraulic actuation mechanism and the orifice area of the parallel valves connection are established first. And then the vibration process is divided into two sections in terms of the direction of the flow, the analytical expression of the excited waveform is solved. Based on relationships exist between working states and the control parameters the analytical results, the vibration boundary positions and the are derived. Finally an experimental system was built to validate the theoretical analysis. It is verified that this electro-hydraulic vibration system could achieve high working frequency, up to 2 000 Hz. The excited waveform is similar to the sinnsoidal waveform. And the ascent and decent slopes of the waveforms are somewhat asymmetrical. This asymmetry is not only caused by the change of the direction of the elastic force but also dependent on the bias position of the vibration. Consequentky the distortion of effective working waveform is less tha~ 10%. This electro-hydraulic vibrator controlled by t

关键词： 2D valves hydraulic multiple-valve system electro-hydraulic vibrator excited waveform

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Natural nitrogen-doped multiporous carbon from biological cells as sulfur stabilizers for lithium-sulfur batteries

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Chinese Chemical Letters 2017年第4期28卷 738-742页

作者： Yan-Ping Xie hong-Wei Cheng Wei Chai hong Yue Xuan Zhang jian-Hui Fang hong-Bin Zhao jia-Qiang Xu College of Science Shanghai University Shanghai 200444 China Department of Material Science and Engineering Shanghai University Shanghai 200444 China Department of Chemical Engineering Zaozhuang Vocational College Zaozhuang 277800 China

In this context,we firstly synthesized a novel nitrogen-doped multiporous carbon material from renewable biological cells through a facile chemical activation with K;CO;.After sulfur impregnation,the carbon/sulfur composite achieved a sulfur content of about 67 wt%.The C/S composite as the cathode of lithium-sulfur batteries exhibited a discharge capacity of 1410 mAh/g and good capacity retention of912 mAh/g at *** outstanding results were attributed to the synergy effect of microporous carbon and natural doping nitrogen *** believe that the facile approach for the synthesis of nitrogen-doped multiporous carbon from the low-cost and sustainable biological resources will not only be applied in lithium-sulfur batteries,but also in other electrode materials.

关键词： Biological cell Multiporous carbon Nitrogen-doped Lithium-sulfur batteries

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北京市市售5类海产品中4种砷形态的监测结果

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职业与健康 2017年第19期33卷 2655-2659页

作者：李敏浦育王紫纹李斯李建红刘佳郭爱华北京市西城区疾病预防控制中心理化检验科北京100120

目的通过对北京市市售5大类海产品中4种形态砷的检测,了解各类海产品的砷污染状况并进行分析评价,以便及时发现相关食品安全隐患。方法按照《国家食品安全风险监测工作手册》中的液相色谱-氢化发生-原子荧光光谱法对海产品中常见的4种... 详细信息

目的通过对北京市市售5大类海产品中4种形态砷的检测,了解各类海产品的砷污染状况并进行分析评价,以便及时发现相关食品安全隐患。方法按照《国家食品安全风险监测工作手册》中的液相色谱-氢化发生-原子荧光光谱法对海产品中常见的4种主要砷化物:亚砷酸(AsⅢ)、砷酸(AsⅤ)、一甲基砷(MMA)和二甲基砷(DMA)进行测定。结果总计检测5大类,83件样品,依照GB 2762-2012《食品中污染物限量》,对有限量标准的39件进行评价,均合格,合格率为100%。部分紫菜和干海带样品无机砷含量较高,浸泡加工的海带无机砷含量远远低于干海带。结论监测到的北京市市售海鱼、甲壳软体类海产品未出现无机砷的污染,但市民还需保持均衡和多元化的饮食,以免因偏食某几类食物而摄入过量砷。

关键词：海产品无机砷一甲基砷二甲基砷

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H_(2)S-based therapies for ischaemic stroke:opportunities and challenges

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Stroke & Vascular Neurology 2019年第2期4卷 63-66页

作者： jia jia Jie Li jian Cheng jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences Soochow UniversitySuzhouJiangsuChina jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience Soochow UniversitySuzhouJiangsuChina

Stroke is a cerebrovascular disease displaying high mortality and morbidity. Despite extensive efforts, only very few therapies are available for stroke patients as yet. Hydrogen sulfide (H2S) is thought to be a signalling molecule that is endogenously produced and plays functional roles in the central nervous system. Currently, numerous studies show that H2S impacts stroke outcomes in animal and cellular models. Here, we review the recent research regarding the effects of endogenously produced H2S as well as exogenous H2S donors on stroke pathology, focusing on the potential of H2S-based therapies in treating ischaemic stroke. We also discuss the several issues that hinder the clinical translation of H2S-based therapies from the bench. Taken together, we think that H2S-based therapies are promising strategies for treating cerebral ischaemia if we successfully address these issues.

关键词： therapies endogenous mortality

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***:An R package for standardizing scientific names of plants and animals

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Plant Diversity 2023年第1期45卷 1-5页

作者： jian Zhang hong Qian Center for Global Change and Complex Ecosystems Zhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal University200241ShanghaiChina Research and Collections Center Illinois State Museum1011 East As SreetSpringfieldI62703USM

The scientific names of organisms are key identifiers of plants and *** treating scientific names is a prerequisite for biodiversity research and ***,we present an R package,’***’,which can standardize and harmonize scientific names in plant and animal species lists at a fast speed and at a high rate of matching *** most of other similar R packages each of which works with only one taxonomic database,*** can work with all taxonomic databases,as long as they are properly *** databases for plants and animals that can be directly used by ***,which include bryophytes,vascular plants,amphibians,birds,fishes,mammals,and reptiles,are available *** can be a very useful tool for botanists,zoologists,ecologists and biogeographers to standardize and harmonize scientific names of organisms.

关键词： Biodiversity informatics Scientific names Species name matching Taxonomic harmonization Taxonomic tool U.Taxonstand

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Effect of quenching-partitioning treatment on the microstructure, mechanical and abrasive properties of high carbon steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 676-687页

作者： jian-ping Lai jia-xin Yu Jiong Wang Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education Mianyang 621010China School of Manufacturing Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Central Sichuan Oil-Gas District Petro-China Southwest Oil and Gas Field CompanySuining 629000China

The present work employed the X-ray diffraction, scanning electron microscopy, electron backscattered diffraction, and electron probe microanalysis techniques to identify the microstructural evolution and mechanical and abrasive behavior of high carbon steel during quenching-partitioning treatment with an aim to enhance the toughness and wear resistance of high carbon *** showed that, with the increase in partitioning temperature from 250 to 400℃, the amount of retained austenite(RA) decreased resulting from the carbide precipitation effect after longer partitioning ***, the stability of RA generally increased because of the enhanced degree of carbon enrichment in *** the factors affecting the toughness of high carbon steel, the stability of RA associated with size, carbon content, and morphology plays a significant role in determining the toughness of high carbon *** analysis of the wear resistance of samples with different mechanical properties shows that hardness is the primary factor affecting the wear resistance of high carbon steel, and the toughness is the secondary one.

关键词： high carbon steel quenching and partitioning microstructural evolution retained austenite

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Ductile damage and simulation of fine-blanking process by FEM

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中国有色金属学会会刊：英文版 2000年第3期10卷 368-371页

作者： ZHANG Xing quan(张兴全) jia jian jun(贾建军) PENG Ying hong(彭颖红) RUAN Xue yu(阮雪榆) Shanghai jiao Tong Univ Natl Die & Mold CAD Engn Res Ctr Shanghai 200030 Peoples R China

Based on the Curson Tvergaard void damage plastic potential equation and by using orthogonal rules of plastic material, the influence of void volume fraction on stress and strain fields was introduced into Levy Mises flow rules. The variation principle of rigid plastic material with void degradation was demonstrated. Furthermore, FEM equations coupled with damage factor were presented to study the void growth and the criterion to judge the damage was also given. Using the developed system, the fine blanking process was simulated and the sheared surface of the part edge was predicted. Meanwhile, the influence of process parameters, such as punch die clearance, V ring force, counter force, radius of punch and die edges, on the height and quality of the sheared surface was analyzed. The calculation results were compared with the experiments, which can be used to guide the design of fine blanking process.

关键词： fine blanking ductile fracture FEM simulation

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Effective Identification and Annotation of Fungal Genomes

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Journal of Computer Science & Technology 2021年第2期36卷 248-260页

作者： jian Liu jia-Liang Sun Yong-Zhuang Liu College of Computer Science Nankai UniversityTianjin 300350China School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China

In the past few decades,the dangers of mycosis have caused widespread *** the development of the sequencing technology,the effective analysis of fungal sequencing data has become a *** the gradual increase of fungal sequencing data,there is now a lack of sufficient approaches for the identification and functional annotation of fungal chromosomal *** overcome this challenge,this paper firstly deals with the approaches of the identification and annotation of fungal genomes based on short and long reads sequenced by using multiple platforms such as Illumina and *** this paper develops an automated bioinformatics pipeline called PFGI for the identification and annotation *** experimental evaluation on a real-world dataset ENA(European Nucleotide Archive)shows that PFGI provides a user-friendly way to perform fungal identification and annotation based on the sequencing data analysis,and could provide accurate analyzing results,accurate to the species level(97%sequence identity).

关键词： fungal genome fungal identification bioinformatics pipeline

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Quality of gastric ulcer healing evaluated by endoscopic ultrasonography

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World Journal of Gastroenterology 2005年第22期11卷 3461-3464页

作者： jian-MinSi QianCao jia-GuoWu GastroenterologyLaboratory InstituteofClinicalMedicineSirRunRunShawHospitalSchoolofMedicineZhejiangUniversityHangzhou310006ZhejiangProvinceChina

AIM: To evaluate the quality of gastric ulcer healing after different antiulcer treatment by endoscopic ultrasonography(EUS).METHODS: The patients were divided into three groups, and received lansoprazole, amoxicillin and clarithromycinfor 1 wk. Then group A took lansoprazole combined with tepreton for 5 wk, group B took lansoprazole and group C took tepreton for 5 wk. Endoscopy and EUS were performed before and 6 wk after medication. RESULTS: There was no significant difference in cumulative healing rate to S stage between the groups (89%, 82%vs83%,P＞0.05). The rate of white scar formation was significantly higher in group A than in groups B and C (67%, 36%, 50%, P＜0.05). The average contraction rates of the width of ulcer crater, length of disrupted muscularis propria layer and hypoechoic area were higher in groupA than in groups B and C (0.792±0.090, 0.660±0.105 vs0.668±0.143, P＜0.05). The hypoechoic area disappeared in four cases of group A, one of group B and two of group C. The percentage of hypoechoic area disappearance was higher in group A than in the other two groups (44%, 9%vs 17%, P＜0.05). Gastric ulcer healing was better ingroup ***: The combined administration of proton pump inhibitors and mucosal protective agent can improve gastric ulcer healing.

关键词： Quality of ulcer healing Endoscopic ultrasono-graphy Gastric ulcer

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Diabetes mellitus is a risk factor of acute kidney injury in liver transplantation patients

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Hepatobiliary & Pancreatic Diseases International 2021年第3期20卷 215-221页

作者： Yu-jia Wang jian-Hua Li Yi Guan Qiong-hong Xie Chuan-Ming Hao Zheng-Xin Wang Division of Nephrology Huashan HospitalFudan UniversityShanghai 200040China Division of General Surgery Huashan HospitalFudan UniversityShanghai 200040China

Background: Diabetes mellitus has become an increasing global health burden with rapid growing prevalence. Patients with diabetes have higher susceptibility to acute kidney injury(AKI). Liver transplantation(LT) predisposes the kidney to injury. However, the association between diabetes and AKI in LT patients remains unclear. Methods: We conducted a retrospective cohort study examining risk factors for AKI in patients undergone orthotopic LT. Potential risk factors including baseline estimated glomerular filtration rate(e GFR), the model for end-stage liver disease(MELD) score, diabetes, hypertension and intraoperative blood loss were screened. The primary endpoint was AKI occurrence. Multivariate logistic regression was used to analyze the association between potential risk factors and AKI. Results: A total of 291 patients undergone orthotopic LT were included in the present study. Among them, 102 patients(35.05%) developed AKI within 5 days after LT. Diabetes was identified as an independent risk factor for AKI. Patients who developed AKI had worse graft function recovery and higher mortality within 14 days after LT compared to those who did not develop AKI. AKI patients with diabetes had a significant decline of e GFR within the first postoperative year, compared with patients who did not develop AKI and who developed AKI but without diabetes. Conclusions: Diabetes is an independent risk factor for AKI after orthotopic LT. AKI is associated with delayed graft function recovery and higher mortality in short-term postoperative period. Diabetic patients who developed AKI after LT experience a faster decline of e GFR within the first year after surgery.

关键词： Acute kidney injury Liver transplantation Diabetes Renal function

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