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Influence of Mixing Conditions on Morphologies and Properties of MMT/Epoxy Resin Composite Materials

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Chemical Research in Chinese Universities 2010年第3期26卷 479-482页

作者： LI Shi-wei CUI ji-wen ZHAO Cheng-ji FU Tie-zhu na Hui Alan G. MacDiarmid Institute College of Chemistry Jilin University Changchun 130012 P. R. China College of Chemistry and Pharmacy Jiamusi University Jiamusi 154000 P. R. China

Montmorillonite（MMT） was directly modified with hexadecyl trimethyl ammonium bromide. The interlayer spacing of the organophilic montmorillonite（organo-MMT） corresponding to the d（001） plane peak was 2.21 nm The influences of the content of organo-MMT and mixing conditions including mixing temperature and mixing time on the intercalation and exfoliation structures of MMT/epoxy resin composites were investigated by wide X-ray diffraction（WXRD）. The X-ray patterns reveal that organo-MMT was intercalated by the epoxy resin during mixing process. Only under certain mixing conditions, could the exfoliation nanocomposites be formed. The mechanical and thermal properties of the composites were measured. The results indicate that the composites have better mechanical properties and higher Tg than those of the pristine epoxy resin.

关键词： Montmorillonite(MMT) Epoxy resin Mixing condition

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连续油管应变疲劳寿命预测

石油管材与仪器 2024年第2期10卷 31-35页

作者：王新虎王坤常昊吉楠纪奇李露中国石油集团工程材料研究院有限公司油气钻采输送装备全国重点实验室陕西西安710077

连续油管疲劳是多向载荷共同作用下的应变疲劳,准确预测其疲劳寿命比较困难,其中如何计算在管内流体内压作用下连续油管弯曲塑性应变是关键点。建立了在弯曲和内压共同作用下连续油管的当量塑性应变估算模型以及表面损伤的连续油管在表... 详细信息

连续油管疲劳是多向载荷共同作用下的应变疲劳,准确预测其疲劳寿命比较困难,其中如何计算在管内流体内压作用下连续油管弯曲塑性应变是关键点。建立了在弯曲和内压共同作用下连续油管的当量塑性应变估算模型以及表面损伤的连续油管在表面缺陷处的塑性应变估算模型,认为管内流体压力和表面缺陷都会增加连续油管的塑性应变,管内流体压力引起连续油管塑性应变的增量随着内压增大呈指数增加,表面缺陷引起连续油管塑性应变的增量也随着缺陷损伤程度呈指数增加。内压大小可以用管内流体压力与连续油管内压强度的比值表征,缺陷损伤程度可以用缺陷的深度、宽度、长度等参量与连续油管有关几何尺寸的比值表征。用疲劳试验方法检验了模型的正确性。可以用Miner疲劳累积线性法则评估连续油管疲劳寿命,焊缝、腐蚀介质等影响因素可以用系数衡量。

关键词：连续油管塑性应变数学模型疲劳寿命预测

Polyphosphate-crosslinked collagen scaffolds for hemostasis and alveolar bone regeneration after tooth extraction

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Bioactive Materials 2022年第9期7卷 68-81页

作者： Jun-ting Gu Kai jiao jing Li jian-fei Yan Kai-yan Wang Fu Wang Yan Liu Franklin R.Tay ji-hua Chen Li-na Niu national Clinical Research Center for Oral Diseases State Key Laboratory of Military StomatologyShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical UniversityXi’anShaanxiChina Department of Endodontics The Dental College of GeorgiaAugusta UniversityAugustaGA30912USA

Post-extraction bleeding and alveolar bone resorption are the two frequently encountered complications after tooth extraction that result in poor healing and rehabilitation *** present study covalently bonded polyphosphate onto a collagen scaffold(P-CS)by *** P-CS demonstrated improved hemostatic property in a healthy rat model and an anticoagulant-treated rat *** improvement is attributed to the increase in hydrophilicity,increased thrombin generation,platelet activation and stimulation of the intrinsic coagulation *** addition,the P-CS promoted the in-situ bone regeneration and alveolar ridge preservation in a rat alveolar bone defect *** promotion is attributed to enhanced osteogenic differentiation of bone marrow stromal *** was improved by both polyphosphate and blood *** together,P-CS possesses favorable hemostasis and alveolar ridge preservation *** may be used as an effective treatment option for post-extraction bleeding and alveolar bone *** of significance:Collagen scaffold is commonly used for the treatment of post-extraction bleeding and alveolar bone loss after tooth ***,its application is hampered by insufficient hemostatic and osteoinductive *** polyphosphate with collagen produces a modified collagen scaffold that possesses improved hemostatic performance and augmented bone regeneration potential.

关键词： Alveolar ridge preservation Blood clotting Osteogenesis Polyphosphate

Effect of Ultra-low Temperature on Carbonation Performance of SFRRC and Prediction Model

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 778-788页

作者：钱维民苏骏 ZHAO jiayu ji Wei School of Civil Engineering and Environment Hubei University of TechnologyWuhan430068China College of Engineering and Technology Hubei University of TechnologyWuhan430068China

Through the rapid carbonation test of SFRRC with different fiber volume fractions at ultralow temperature,the influence of ultra-low temperature damage on the carbonation resistance of SFRRC was analyzed,which provides a theoretical basis for the application of SFRRC in ultra-low temperature *** experimental results show that ultra-low temperatures can significantly weaken the carbonization resistance of *** the temperature reaches 160℃,the carbonization depth increases by 67.66%compared with the normal *** proper amount of steel fiber has an evident influence on the carbonation resistance of the ***,when the addition amount exceeds the optimum content,the carbonation resistance of the material *** grey prediction model established by constructing the original sequence can reasonably predict the carbonation resistance of SFRRC after ultra-low temperatures.

关键词： ultra-low temperature SFRRC carbonization grey model

Synthesis of Mesoporous Silica and Ti-containing Molecular Sieves via A Novel Assembly

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Chinese Chemical Letters 2001年第8期12卷 737-740页

作者： jing xin ji Shuan SUO Xiao Ming ZHANG State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000

Thermally stable mesoporous silica and Ti-containing molecular sieves have been synthesized at mild temperature using low-cost and biodegradable --- amphoteric tetradecyl betaine as template. The physicochemical chara... 详细信息

关键词： Synthesis meosoporous silica and Ti-containing molecular sieves amphoteric tetradecyl betaine novel assembly.

Abandonment and Recovery Operation of Steel Lazy-Wave Riser in Deepwater by Controlled Vessel and Cable Velocity Rate

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China Ocean Engineering 2023年第1期37卷 29-41页

作者： GU ji-jun HUANG Jun GAO Lei CHEN Lei-lei jiA ji-chuan WANG Shu-jiang College of Mechanical and Transportation Engineering China University of Petroleum-BeijingBeijing 102249China CNOOC Research Institute Beijing 100028China

Evaluation of abandonment and recovery operation of steel lazy-wave riser in deepwater is presented in this *** calculation procedure includes two single continuous SLWR and cable segments, which are coupled together to form the overall mathematical model. Then the equilibrium equations of SLWR and cable are established based on minimum total potential energy principle. The coupled equations are discretized by the finite difference method and solved by Newton-Raphson technique in an iterative manner. The present method is validated by well-established commercial code OrcaFlex. Recovery methods by considering different ratios of vessel’s moving velocity to cable’s recovery velocity are evaluated to optimize the abandonment and recovery operation. In order to keep the tension more stable during the recovery process, the rate ratio before leaving the seabed is increased, and the rate ratio after leaving the seabed is reduced.

关键词： steel lazy-wave riser abandonment recovery

The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection

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World Journal of Emergency Medicine 2022年第3期13卷 202-207页

作者： Yuan-li Lei Wen-xing Song Yi Lin Hui-ping Li He-ping Lyu jiao-zhen Chen Zhang-ping Li jia-na Yin ji-ke Xue Shou-quan Chen Department of Emergency Medicine the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Radiology the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Gastroenterology the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Vascular Surgery the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Electrocardiogram Wenzhou People's HospitalWenzhou 325000China

BACKGROUND:Spontaneous isolated superior mesenteric artery(SMA)dissection(SISMAD)is a rare cause of abdominal *** aim of the study is to investigate the role of a new parameter,the ratio of the SMA diameter to the superior mesenteric vein(SMV)diameter(SMA/SMV)based on non-enhanced computed tomography(CT),in the early diagnosis of ***:In a registry study from December 2013 to June 2021,97 abdominal pain SISMAD patients(SISMAD group)admitted to our hospital were ***,the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control ***’s t-test,Wilcoxon rank-sum test,and Chi-square test were used to compare differences between the SISMAD and control *** Calc was used to generate receiver operating characteristic(ROC)***:A total of 291 abdominal pain patients,including 97 SISMAD patients and 194 nonSISMAD patients,were included in the current *** maximum SMA diameter,perivascular exudation,and SMA/SMV based on non-enhanced CT were significant between the two groups(all P<0.05).ROC curves showed that for the maximum SMA diameter,the area under the curve(AUC),cut-off,sensitivity,and specificity were 0.926,9.80,93.8%,and 79.4%,*** SMA/SMV,its AUC,cut-off,sensitivity,and specificity were 0.956,0.83,88.7%,and 92.3%,*** diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter(P<0.05).The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency(AUC=0.970).CONCLUSION:SMA/SMV may be a potential marker for SISMAD.

关键词： Abdominal pain Spontaneous isolated superior mesenteric artery dissection Computed tomography Receiver operating characteristic curve

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基于二阶锥凸松弛的海上风电场内部无功优化

电力建设 2024年第1期45卷 92-101页

作者：张磊姜贞强倪佳华周胡陆艳艳项基中国电建集团华东勘测设计研究院有限公司杭州市311122 浙江大学电气工程学院杭州市310027

为了减少海上风电场有功网损,提出一种基于二阶锥凸松弛的海上风电场无功出力优化模型。该模型考虑最优潮流过程中所涉及的电网稳定要求与安全裕度,在各风机最大化有功出力的前提下,优化各风机无功出力,以减少网损,提高风场整体出力。... 详细信息

为了减少海上风电场有功网损,提出一种基于二阶锥凸松弛的海上风电场无功出力优化模型。该模型考虑最优潮流过程中所涉及的电网稳定要求与安全裕度,在各风机最大化有功出力的前提下,优化各风机无功出力,以减少网损,提高风场整体出力。通过二阶锥凸松弛的数学优化方法,解决多种约束下的潮流优化问题,给出了最大化风电场整体有功出力下的各风机无功出力最优值。最后,以舟山普陀海上风电场为例,对各机组无功出力进行了优化,并与基于启发式的粒子群优化算法和经典的内点法优化算法进行了对比,结果表明所提算法能明显减少系统有功损耗,提升风电场整体有功出力。

关键词：海上风电场无功优化最优潮流凸优化

Grain yield and water use of winter wheat as affected by water and sulfur supply in the North China Plain

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Journal of Integrative Agriculture 2017年第3期16卷 614-625页

作者： XIE Ying-xin ZHANG Hui ZHU Yun-ji ZHAO Li YANG jia-heng CHA Fei-na LIU Cao WANG Chen-yang GUO Tian-cai State Key Laboratory of Wheat and Maize Crop Science Henan Agricultural University Zhengzhou 450002 P.R.China College of Resources and Environment Henan Agricultural University Zhengzhou 450002 P.R. China Zhoukou Academy of Agricultural Sciences Zhoukou 466001 P.R. China Zhengzhou Meteorological Bureau Zhengzhou 450000 P.R. China

Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may not be readily available in the situation of *** of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water *** objective of this study was to explore effects of irrigation and sulphur（S）application on water consumption,dry matter accumulation（DMA）,and grain yield of winter wheat in *** irrigation regimes including no irrigation（rainfed,I0）during the whole growth period,once irrigation only at jointing stage（90 mm,I1）,and twice respective irrigation at jointing and anthesis stages（90 mm plus 90 mm,I2）,and two levels of S application including 0S0and 60 kg ha^–1（S60）were designed in the field experiment in *** showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5–23.7%and nitrogen partial factor productivity（NPFP）by 21.2–45.0%in two wheat seasons,but markedly decreased crop water use efficiency（YWUE）.Furthermore,S supply 60 kg ha^–1 significantly increased mean grain yield,YWUE,IWUE and NPFP by 5.6,6.1,23.2,and 5.6%（across two wheat seasons）,***,we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of ***,water supply is still the most important factor to restrict the growth of wheat in the present case of NCP,supplying 60 kg ha^–1 S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.

关键词： sulphur irrigation winter wheat grain yield water use efficiency 1