检索结果-南通市图书馆

China Foundry 2018年第4期15卷 283-290页

作者： yu-guang zhao zhe wang xiao-feng xu ming-zhe zhang wen-qiang jiang key laboratory of automobile of ministry of Education ＆school of Materials Science and Engineering Nanling Campusjilin UniversityNO.5988 Renmin streetchangchun 130025china

In the present work, a unique gradient cooling heat treatment process(GCHT) for a Mn-Si-Cr-B bainitic cast steel was developed, and microstructure and mechanical properties were examined by OM, SEM, EBSD and a uniaxial tensile test. The results showed that the structural-gradient-material(SGM) with a gradient microstructure from granular bainite to martensite was successfully produced, and it exhibited a good ductility(~13.8%) at one end and an excellent ultimate strength(~1,720 MPa) at the other end. In between the bainite and martensite, a transition region with a superior combination of tensile strength and ductility(1,700 MPa and 11.1%) was obtained, which is different from the normal knowledge of a brittle transition region. Moreover, through changing the gradient of cooling rate, the optimized SGM with a new gradient microstructure from pearlite to martensite showed a more stable structural gradient and an improved ductility(22.8%) at one end. The microstructure variation in the sample was mainly related to the carbon diffusion rate during heat treatment, and the diffusion rate could be controlled by regulating the cooling velocity. Therefore, the SGMs with different gradient microstructures could be designed to meet the needs of different properties. As a result, this work provides a new approach for preparation of the gradient structured steel, which has potential for practical application for dual-property automobile parts.

关键词： bainitic cast steel gradient cooling heat treatment structural-gradient-materials

Long-term outcomes of choledochoduodenostomy for hepatolithiasis

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2010年第2期123卷 137-141页

作者： LING xiao-feng xu Zhi WANG Li-xin HOU Chun-sheng XIU Dian-rong ZHANG Tong-lin ZHOU xiao-si Department of General Surgery Peking University' Third Hospital. Beijing 100191 China

Background Oddi sphincter plays an important role in preventing reflux cholangitis. There exists the controversy on application of choledochoduodenostomy in hepatolithiasis management. The present study aimed at evaluating long-term outcomes of choledochoduodenostomy for the treatment of hepatolithiasis. Methods Forty-six consecutive cases of hepatolithiasis who underwent choledochoduodenostomy were analyzed retrospectively. The pre- and postoperative rates of recurrent cholangitis and acute cholangitis severe type were compared. Paired chi-square test was applied. Results The mean follow-up time was 17.3 years ranging from 1.6 to 40 years with a follow-up rate of 97.8% （45/46）. High rates of remnant stones （39.1%, 18/46）, recurrent stones （31.1%, 14/45）, uncorrected strictures （85%, 17/20）, and mortality （24.4%, 11/45） were observed in this group. Regurgitation of food debris and duodenal content into the biliary tract through the anastomosis was observed. The rate of recurrent cholangitis was equal to the preoperative period （93.3%, 42/45）. The rate of acute cholangitis severe type after choledochoduodenostomy （46.7%, 21/45） increased significantly （P 〈0.01） when compared to the preoperative period （20.0%, 9/45）. Conclusions Choledochoduodenostomy did not entirely achieve the goal of clearance of stones, correction of strictures, and removing of hepatobiliary lesions by itself. Chofedochoduodenostomy without cholangioplasty resulted in an increase of severe reflux cholangitis due to the loss of the anti-reflux function of the sphincter of Oddi. Therefore, choledochoduodenostomy is not an ideal approach to reduce cholangitis in hepatolithiasis and is not the best choice in the management of hepatolithiasis.

关键词： hepatolithiasis choledochoduodenostomy long-term outcome

Ship-in-bottle formation of Ru_3(CO)_(12) in NaY zeolite

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1994年第3期12卷 258-264页

作者： xiao, feng-Shou xu, Ru-Ren HE, Ya-Nan Department of Chemistry, Jilin University, Changchun, Jilin 130023, China Department of Chemistry Jilin University Changchun Jilin 130023 China

NaY zeolite entrapped Ru3(CO)12 cluster has been synthesized from RuCl3 ion-exchanged NaY, which is well characterized by IR and Raman spectroscopies and CO chemisorp-tion. When the Ru3+/NaY sample is heated from 298 K to 393 K for 25 h and for 10 h at 393 K, the sample colour changes from dark to brown-yellow. The in situ infrared spectrum exhibits absorption bands at 2130, 2064, 2040, 2017, 1990, 1953 and 1925 cm-1. The bands at 2130 cm-1 arises from the Runm+(CO)l m =1-3;n = 1 - 3; l = 1-12). The bands at 2064, 2040, 2017 and 1990 cm-1 are proposed to be associated with the Ru3(CO)12/NaY, which are close to Ru3(CO)12 crystalline. Furthermore, the Raman results provide bands at 150 and 185 cm-1, which can be attributed to Ru-Ru bonds of the sample as in the case of Ru3(CO)12 crystalline, for which the A1' Ru-Ru stretching mode is assigned to 185 cm-1 and E1' Ru-Ru stretching mode is assigned to a band at 150 cm-1, respectively. CO chemisorption of [Ru3]/NaY gives a CO/Ru ratio of 3.85, which is similar to the stoichiometry of Ru3(CO)12.

关键词： Cluster ruthenium carbonyl NaY zeolite infrared Raman CO chemisorption.

Arabidopsis AT-hook Protein TEK Positively Regulates the Expression of Arabinogalactan Proteins for Nexine Formation

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2015年第2期8卷 251-260页

作者： Qi-Shi dia Jun Zhu xiao-feng xu Yue Lou Zhan-Lin Zhang Zhi-Ping Zhang Zhong-Nan Yang College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China National Key Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China College of Agriculture Henan University of Science and Technology Luoyang 471003 China

Nexine is a conserved layer of the pollen wall. We previously reported that the nexine layer is absent in the knockout mutant of Arabidopsis TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK （TEK） gene. In this study, we investigated the molecular regulatory functions of TEK in pollen development and identified the genes encoding Arabinogalactan proteins （AGPs） as direct targets of TEK, which are essential for nexine formation. Phenotypic similarity between tek and the TEK-SRDX transgenic lines suggest that TEK plays a role in transcriptional activation in anther development. Microarray analysis identified a total of 661 genes downregulated in tek, including four genes encoding AGPs, AGP6, AGP11, AGP23, and AGP40. Electrophoretic mobility shift assays showed that TEK could directly bind the nuclear matrix attachment region （MAR） and the promoter of AGP6. Chromatin immunoprecipitation followed by PCR analysis demonstrated that TEK is enriched in the promoters of the four AGP genes. Expression of AGP6 driven by the TEK promoter in tek partially rescued both nexine formation and plant fertility. These results indicate that TEK directly reg- ulates AGP expression in the anther to control nexine layer formation. We also proposed that glycoproteins might be essential components of the nexine laver in the oollen wall.

关键词： cell walls development pollen development nexine

Fast nuclear-spin gates and electrons−nuclei entanglement of neutral atoms in weak magnetic fields

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第2期19卷 179-203页

作者： xiao-feng Shi School of Physics Xidian UniversityXi’an 710071China

We present a novel class of Rydberg-mediated nuclear-spin entanglement in divalent atoms with global laser ***,we show a fast nuclear-spin controlled phase gate of an arbitrary phase realizable either with two laser pulses when assisted by Stark shifts,or with three ***,we propose to create an electrons−nuclei-entangled state,which is named a super bell state(SBS)for it mimics a large Bell state incorporating three small Bell ***,we show a protocol to create a three-atom electrons-nuclei entangled state which contains the three-body W and Greenberger−Horne−Zeilinger(GHZ)states *** protocols possess high intrinsic fidelities,do not require single-site Rydberg addressing,and can be executed with large Rydberg Rabi frequencies in a weak,Gauss-scale magnetic *** latter two protocols can enable measurement-based preparation of Bell,hyperentangled,and GHZ states,and,specifically,SBS can enable quantum dense coding where one can share three classical bits of information by sending one particle.

关键词： nuclear-spin qubit electrons−nuclei entanglement super Bell state Greenberger−Horne−Zeilinger state Rydberg-mediated entanglement quantum dense coding

Surface Polarization Effects on Collapse Transition of Polyelectrolyte Brushes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第9期42卷 1313-1320,I0006页

作者： xiao-Fei xu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China

Polyelectrolyte brushes(PEBs)are commonly used to modify surface that have attracted great research *** dielectric permittivity of the grafted surface is typically significantly different from that of solution,which results in surface polarization(SP)effect with a jump of electric *** is thus important to study how SP alters the PEB’s structure and *** this work,the SP effects on PEB structure was studied using a statistical thermodynamic *** free energy functional to describe SP effect was constructed by using the image-charge ***,the electrostatic potential was solved from a modified Poisson-Boltzmann equation taking the ion solvation effect into *** the absence of SP,the thickness of PEB exhibited a continuous collapse transition when decreasing the solvent *** the presence of SP,the collapse became a jump-like *** energy analysis showed that the long-range Coulombic interaction dominated the transition because of the enhanced counterion condensation in the presence of *** theory provides an effective tool to study SP effect on PEBs,and the results explain the underlying physics in PEB collapse transition.

关键词： Surface polarization Polyelectrolyte brush Image charge Ion solvation Polyelectrolyte collapse transition

Progress in processing of porous titanium:a review

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 1932-1955页

作者： xiao-Li Yang Xian-feng Du Zhi-Lin xu Zhong-Shuai Liang Li-Long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Synthesis,Style Editing,and Animation of 3D Cartoon Face

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第2期29卷 506-516页

作者： Ming Guo feng xu Shunfei Wang Zhibo Wang Ming Lu Xiufen Cui xiao Ling School of Software and BNRist Tsinghua UniversityBeijing 100084China Department of Multimedia and Smart Guangdong OPPO Mobile Telecommunications Corp.Ltd.Dongguan 523860China Intel Labs IntelBeijing 100089China

As a popular kind of stylized face,cartoon faces have rich application *** is challenging to create personalized 3D cartoon faces directly from 2D real ***,in order to adapt to more application scenarios,automatic style editing,and animation of cartoon faces is also a crucial problem that is urgently needed to be solved in the industry,but has not yet had a perfect *** solve this problem,we first propose“3D face cartoonizer”,which can generate high-quality 3D cartoon faces with texture when fed into 2D facial *** contribute the first 3D cartoon face hybrid dataset and a new training strategy which first pretrains our network with low-quality triplets in a reconstruction-then-generation manner,and then finetunes it with high-quality triplets in an adversarial manner to fully leverage the hybrid ***,we implement style editing for 3D cartoon faces based on k-means,which can be easily achieved without retrain the neural *** addition,we propose a new cartoon faces'blendshape generation method,and based on this,realize the expression animation of 3D cartoon faces,enabling more practical *** dataset and code will be released for future research.

关键词： cartoon 3D face animation computer graphics

Efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： Han-yu xu Lin-na Wu Yuan Zhang Te Ba xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

Background:Electroacupuncture is often used to treat ***:To evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including PubMed,Cochrane Library,Embase,Web of Science,Chinese Biomedical Literature Database,China National Knowledge Infrastructure,Wanfang Data and VIP Fulltext e-Journals Database were searched up to January 15,*** criteria:Randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:The full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (Pittsburgh Sleep Quality Index[PSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:Thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the PSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];P<0.001).There was no significant difference in the incidence of adverse events between the EA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];P=0.117).In addition,the regression results revealed t

关键词： Electroacupuncture Insomnia Systematic review Meta-analysis

Unconventional Fluorescent and Multi-responsive Polyethyleneimine with LCST and UCST Behavior:Synthesis,Characterization and Biological Applications

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第6期42卷 826-837页

作者： feng-Ming Yin Li-Li Wu Shu-Sheng Li xiao-Na Pan xiao-Li Zhu xu-Bao Jiang Xiang Zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Shandong Institute for Product Quality Inspection Jinan250102China College of Chemical Engineering Tianjin UniversityTianjin300072China

Non-aromatic fluorescent and multi-responsive materials,exhibiting inherent fluorescence emission and controlled phase change,have garnered significant attention in recent ***,the underlying interaction between their fluorescent properties and phase transition remains *** this study,we synthesized a series of catalyst-free aza-Michael addition-based polyethyleneimine(RFPEI)materials by reacting polyethyleneimine(PEI)with N-isopropyl acrylamide(NIPAM).The resulting RFPEI was comprehensively characterized,and demonstrated dual-phase transition behavior(LCST and UCST)in water,which could be finely tuned by adjusting its composition or external factors such as ***,upon UV irradiation(365 nm),RFPEI exhibited strong fluorescence *** further investigated the effects of NIPAM grafting percentage to PEI,polymer concentration,and pH on the LCST/UCST and fluorescent properties of RFPEI aqueous ***,we showcased the great potential of RFPEI as a versatile tool for physiological cell imaging,trace detection,and controlled release of *** study presents a novel class of stimuli-responsive fluorescent materials with promising applications in the field of biomedicine.

关键词： Polyethyleneimine Multi-responsiveness Intrinsic fluorescence emission Cell imaging Controlled drug release