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碳化混凝土孔隙结构与Autoclam气体渗透性能的关联性研究

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材料导报 2023年第8期37卷 46-50页

作者：张铖王玲姚燕史鑫宇中国建筑材料科学研究总院有限公司绿色建筑材料国家重点实验室北京100024

将C30混凝土试件在20%(体积分数)CO_(2)中加速碳化至不同龄期,采用Autoclam测试系统和压汞法(MIP)测试碳化混凝土的空气渗透系数(kAu)及孔隙结构参数,通过灰色关联分析(GRA)研究了二者的关系。结果表明:随碳化时间延长,混凝土的kAu呈指... 详细信息

将C30混凝土试件在20%(体积分数)CO_(2)中加速碳化至不同龄期,采用Autoclam测试系统和压汞法(MIP)测试碳化混凝土的空气渗透系数(kAu)及孔隙结构参数,通过灰色关联分析(GRA)研究了二者的关系。结果表明:随碳化时间延长,混凝土的kAu呈指数式增长,混凝土孔隙率、特征孔径和孔隙连通度也增大,孔径小于200 nm孔的体积占比逐渐减小,200~1 000 nm孔的体积占比逐渐增大,小于1 000 nm孔的体积占比基本不变。GRA结果显示,与碳化混凝土kAu关联度最高的三个孔隙结构参数是:50~200 nm孔的体积占比(γi=0.932)、孔隙连通度(γi=0.907)和孔隙率(γi=0.888),回归建立了kAu与这三个参数之间的线性关系模型,为后期利用kAu建立混凝土寿命预测模型奠定了基础。

关键词：混凝土加速碳化孔隙结构空气渗透系数灰色关联分析

Hydrothermal Synthesis of V-Cr-Al-O Nanospheres and Their Effect on Decomposition of Ammonium Perchlorate

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1460-1462页

作者： YU yao LIN Bin LI Xiongjian Hubei Sanjiang Aerospace jianghe Chemical Technology Co. Ltd.Tichang 444200China First military Representative Office of Rocket Army Equipment Department in Wuhan Wuhan 430040China College of Chemistry and Chemical Engineering Hubei Normal UniversityHuangshi 435002China

V-Cr-Al-O nanospheres were successfully synthesized using V2O5, Al(OH)3, CrO3, and H2C2O4·H2O as the starting materials by a facile one-pot hydrothermal approach. Several techniques containing X-ray powder diffraction, hydrogen temperature programmed reduction, scanning electron microscopy were used to characterize the composition, morphology and redox property of V-Cr-Al-O nanospheres. The catalytic behavior of prepared nanospheres on the thermal decomposition of AP was investigated by the thermogravimetric analysis and differential thermal analysis(TG/DTA). The experimental results show that the thermal decomposition temperature of AP in the presence of V-Cr-Al-O nanospheres is to 395 ℃(decreased by 35 ℃), which proves better catalyst for the thermal decomposition of AP.

关键词： V-Cr-Al-O nanospheres catalysis hydrothermal synthesis ammonium perchlorate

Fast Smooth Second-Order Sliding Mode Control with Disturbance Observer for Automatic Shell Magazine

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Journal of Shanghai Jiaotong university(Science) 2021年第6期26卷 847-856页

作者： yao Laipeng HOU Baolin LIU Xi School of Mechanical Engineering Changshu Institute of TechnologySuzhou 215500JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This paper studies practical control design for a novel automatic shell magazine(ASM)with a new fast smooth second-order sliding mode(FSSOSM)control based on disturbance *** dynamic model of the ASM with parameter perturbations and nonlinear friction is established.A higher order sliding mode disturbance observer based on super-twisting algorithm is utilized as a robust compensator to estimate the lumped *** proposed FSSOSM control is performed to obtain the continuous sliding mode control law and inhibit the chattering *** finite time convergence is investigated by utilizing the Lyapunov stability *** controllers,the traditional sliding mode controller,the proposed FSSOSM controller and a continuous fixed-time second-order sliding mode(CFTSOSM)controller,are *** comparative simulation results under three typical working conditions(no-loaded,half-loaded and full-loaded)demonstrate that the proposed control strategy has a high dynamic tracking performance along with a good robustness against model uncertainty.

关键词： nonlinear systems model uncertainty disturbance observer finite-time convergence sliding mode control

A huge pancreatic lipoma mimicking a well-differentiated liposarcoma: A case report and systematic literature review

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World Journal of Clinical Cases 2019年第16期7卷 2352-2359页

作者： Ren-Yi Xiao Xing yao Wei-Lin Wang Division of Hepatobiliary and Pancreatic Surgery Department of General SurgeryThe Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Department of General Surgery Huzhou Central HospitalHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Pancreatic lipomas are thought to be very *** are usually easy to identify on imaging,particularly via computed tomography (CT).But sometimes it’s quite difficult to distinguish a lipoma from a well-liposarcoma without histologic *** SUMMARY Here,we present a case of pancreatic lipoma in a 59-year-old *** was asymptomatic and had no medical history of *** and magnetic resonance imaging revealed a mass like well-differentiated liposarcoma in the pancreatic head,positron emission tomography/CT showed a low fluorodeoxyglucose uptake and laboratory tests revealed elevated transaminase and carbohydrate antigen-199 ***,the patient underwent a ***,mature adipocytes were noted in the bulk of the ***,the pathologic diagnosis of the pancreatic neoplasm was *** our knowledge,this case is the first example of a suspected well-differentiated liposarcoma that was actually a pancreatic *** also highlight the radiological features distinguishing a pancreatic lipoma from a pancreatic liposarcoma and briefly review the *** Pancreatic lipomas show no obvious gender bias and most commonly occur in the head of the pancreas,of which the maximum diameters are often less than 5 cm,and small,asymptomatic non-compressed lipomas require follow-up *** excision should be considered when the tumor has compressed important tissues or is difficult to distinguish from a liposarcoma,the choice of surgery depends on the intraoperative presentation.

关键词： Pancreatic Lipoma Liposarcoma Pancreas Case report

Uterine incision dehiscence 3 mo after cesarean section causing massive bleeding:A case report

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World Journal of Clinical Cases 2020年第11期8卷 2392-2398页

作者： yao Zhang Ning-Ye Ma Xiao-Ao Pang Department of Obstetrics and Gynecology Shengjing Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND The traditional definition of late postpartum hemorrhage is a massive uterine hemorrhage from 24 h after delivery to the puerperal ***,we report a case of late postpartum hemorrhage that occurred 3 mo after cesarean section and endangered the patient's *** cause of the case we are reporting was poor incision *** reporting this case,we hope to make doctors aware that late postpartum hemorrhage due to poor incision healing may happen as late as 3 mo after cesarean *** SUMMARY A 31-year-old woman complained of acute,severe vaginal bleeding for 1 h;the patient had a history of cesarean section 3 mo *** receiving antiinflammatory treatment,fluid supplementation,blood transfusion,oxytocin administration,and hemostatic treatment,the vaginal bleeding ceased,and the patient’s clinical status ***,she experienced recurrent massive vaginal bleeding,and uterine contractile agents did not decrease the persistent *** save the patient’s life,she was admitted for emergency *** exploratory laparotomy,dehiscence and necrosis of the previous cesarean section scar were noted;the dehiscence penetrated through the entire thickness of the uterine muscle wall and extended to the left uterine ***,we performed a total *** Late postpartum hemorrhage due to poor incision healing after cesarean section may occur in the 3 mo after cesarean section or even ***,obstetricians-gynecologists should monitor for this potential complication in all patients post–cesarean *** hemorrhages can be severe enough to endanger the patient's life.

关键词： Cesarean section Late postpartum hemorrhage Pathogeny Prevention Treatment Wound healing Case report

Metabolic disorders of fatty acids and fatty acid amides associated with human gastric cancer morbidity

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Chinese Medical Journal 2012年第5期125卷 757-763页

作者： SONG Hu PENG Jun-sheng yao Dong-sheng LIU Da-ling YANG Zu-li DU Yan-ping XIANG Jun Department of Gastrointestinal Surgery Xuzhou Central Hospital（Affiliated Hospital of Medical College of Southeast University）Xuzhou Jiangsu 221009 China Department of Gastrointestinal Surge% Sixth Affiliated Hospital（Gaslrointestinal ＆ Anal Hospital） Sun Yat-sen University GuangzhouGuangdong 510655 China National Engineering Research Center of Genetic Medicine Ji NanUniversity Guangzhou Guangdong 510632 China

Background Gastric cancer （GC） is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fat... 详细信息

关键词： gastric cancer fatty acids amides metabolic disorders

Closed-form solution for dynamic responses of shaft-tunnel junction under uniform P waves

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Underground Space 2022年第3期7卷 352-362页

作者： Jinghua Zhang Yong Yuan Mingqing Xiao yao Yin a Qing Sun Department of Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China China Railway Siyuan Survey and Design Group Co. Wuhan 430063China

This paper discusses the special situation when a shaft-tunnel junction is subject to vertically propagating P *** a complicated system like the shaft-tunnel junction,it is necessary to investigate the most basic cases firstly,and the responses induced by uniform P waves are one of *** this end,a closed-form solution is derived from the classical differential equation describing the forced vibration of a single degree-of-freedom *** key issue is the characterization of the coupled dynamic interactions among the shaft,the tunnel,and the *** paradigm regards the three of them as a massive rigid body,a continuous Euler-Bernoulli beam,and a set of supporting elements,*** final solution is to calculate the displacements of the shaft and the tunnel in the form of two compact equations,and the internal forces of the tunnel are therefore easily *** means of a finite element simulation,the validity as well as the accuracy of the closed-form solution is *** solution provides an explicit comprehension of the coupled dynamic interactions and thus enhances the understanding of the dynamic mechanics of the shaft-tunnel junction.

关键词： Shaft-tunnel junction Dynamic responses Closed-form solution P waves

Personalized News Recommendation Based on the Text and Image Integration

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Computers, Materials & Continua 2020年第7期64卷 557-570页

作者： Kehua Yang Shaosong Long Wei Zhang Jiqing yao Jing Liu College of Computer Science and Electronic Engineering and Key Laboratory for Embedded and Network Computing of Hunan Province Hunan UniversityChangsha410082China Oath Verizon Company New York10007USA

The personalized news recommendation has been very popular in the news recommendation *** most research,the picture information in the news is ignored,but the information conveyed to the users through pictures is more intuitive and more likely to affect the users’reading interests than the one in the textual ***,in this paper,a model that combines images and texts in the news is *** this model,the new tags are extracted from the images and texts in the news,and based on these new tags,an adaptive tag(AT)algorithm is *** AT algorithm selects the tags the user is interested in based on the user *** particular,the AT algorithm can predict tags that a user may be interested in with the help of the tag correlation graph without any user *** proposed AT algorithm is verified by *** experimental results verified the AT algorithm regarding three evaluation indexes F1-score(F1),area under curve(AUC)and mean reciprocal rank(MRR).The recommended effect of the proposed algorithm is found to be better than those of the various baseline algorithms on real-world datasets.

关键词： News recommendation F1 AUC MRR feedback correlation graph

Numerical Validation for High Order Hyperbolic Moment System of Wigner Equation

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Communications in Computational Physics 2014年第3期15卷 569-595页

作者： Ruo Li Tiao Lu Yanli Wang Wenqi yao School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China HEDPS and LMAM Peking UniversityBeijing 100871P.R.China BICMR Peking UniversityBeijing 100871P.R.China CAPT Peking UniversityBeijing 100871P.R.China

A globally hyperbolic moment system upto arbitrary order for the Wigner equation was derived in[6].For numerically solving the high order hyperbolic moment system therein,we in this paper develop a preliminary numerical method for this system following the NRxx method recently proposed in[8],to validate the moment system of the Wigner *** method developed can keep both mass and momentum conserved,and the variation of the total energy under control though it is not strictly *** systematically study the numerical convergence of the solution to the moment system both in the size of spatial mesh and in the order of the moment expansion,and the convergence of the numerical solution of the moment system to the numerical solution of the Wigner equation using the discrete velocity *** numerical results indicate that the high order moment system in[6]is a valid model for the Wigner equation,and the proposed numerical method for the moment system is quite promising to carry out the simulation of the Wigner equation.

关键词： Wigner equation NRxx method moment method