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Application of Neural Network in Precision Prediction of hat-Section Profiles in Rotary Draw Bending

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Journal of Materials Science & Technology 2001年第1期17卷 137-138页

作者： Li X.C. yang y.y. Jin Z.h. Liu J.T. Li S.P. harbin Inst. of Technol. Harbin 150001 China

It is difficult to control the accuracy of hat-section profile rotary-draw bent products because their shapes are complex and many factors influence the forming process. A multi-layer feed-forward neural network based on improved BP (back propagation) algorithm is adopted to study the influence law of the main material properties and forming parameters on the accuracy of hat-section profile forming process. The prediction of rotary draw-bending precision is realized and the technology parameters in the forming process are controlled according to the given precision.

关键词： Application of Neural Network in Precision Prediction of hat-Section Profiles in Rotary Draw Bending

Porous Assembly of Metallo-Supramolecule and Polyoxometal-ate via Ionic Complexation with Vapor Sorption Properties

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Chinese Journal of Chemistry 2022年第7期40卷 813-818页

作者： yaping xu hao yu Xin Jiang Junjuan Shi Bao Li Lu Li Lixin Wu Ming Wang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunJilin 130012China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunJilin 130012China

Porous materials have been extensively developed and displayed special applications in diverse fields,however,it still remains a great challenge in developing new synthetic methods with features of energy-saving and *** this study,we reported the construction of a series of novel ionic complexes based on discrete supramolecular triangle structure and polyoxometalate[Mo_(6)O_(19)]^(2-),using a quite efficient *** obtained composites exhibit precise 3D network structures with ideal stability con-taining micropores,which were characterized by the 1h NMR,ESI-MS,TEM,SEM,and single-crystal X-ray *** compo-sites showed differential vapor adsorption behaviors for benzene,toluene,and *** work provides a novel approach for fabricating porous materials through electrostatic interactions and has great potential for gas separation.

关键词： Self-assembly Metallo-supramolecule Polyoxometalates Electrostatic interactions Vapor sorption

跖趾关节融合联合跖趾关节成形术治疗老年类风湿前足畸形的短期疗效研究

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湖南师范大学学报（医学版） 2024年第1期21卷 110-114页

作者：宋铁楠赵德源佟勇剑宋波徐刚徐州医科大学附属连云港市第一人民医院创伤骨科连云港222002 锦州医科大学锦州121012

目的:探究跖趾关节融合联合跖趾关节成形术治疗老年类风湿前足畸形的短期疗效比较。方法:选取2019年7月至2022年7月我院收治的92例老年类风湿前足畸形患者作为本研究对象,患者均接受跖趾关节融合跖趾关节成形术治疗。对患者进行一年随访... 详细信息

目的:探究跖趾关节融合联合跖趾关节成形术治疗老年类风湿前足畸形的短期疗效比较。方法:选取2019年7月至2022年7月我院收治的92例老年类风湿前足畸形患者作为本研究对象,患者均接受跖趾关节融合跖趾关节成形术治疗。对患者进行一年随访,观察患者术前术后拇外翻角(hVA)、第1—2跖骨间角(IMA)变化情况,记录比较术前术后患者的美国足踝外科协会(AOFAS)评分、足底压力情况、疼痛评分(VAS)、Berg平衡量表(BBS)评分、改良Barthel指数(MBI)评分及患者的生活质量评分。结果:与术前比较,术后患者的hVA、IMA均降低,疼痛、功能、足趾力线及AOFAS总分均升高,足底各部分压力均减小,VAS评分降低,BBS评分和MBI评分均升高,生活质量各维度评分均较术前升高。随访期间,92例患者中出现1例术后第1跖趾关节骨不连,3例切口延迟愈合,未发生伤口感染、足趾坏死、复发、形成跖底胼胝等情况。结论:跖趾关节融合联合跖趾关节成形术对老年类风湿前足畸形患者短期疗效显著,可以降低患者的hVA和IMA,改善患者的疼痛情况,减轻足底压力,提高生活质量,能够有效地改善老年类风湿前足畸形患者的结构和功能障碍。

关键词：跖趾关节融合术跖趾关节成形术老年类风湿前足畸形

复合改性纳米TiO_(2)催化降解五氯苯酚的试验研究

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工业用水与废水 2024年第3期55卷 50-55页

作者：赵连波张瑶瑶常丹李梦耀许小英核工业二〇三研究所西安710100 陕西理工大学材料科学与工程学院矿渣综合利用与环境技术国家地方联合工程实验室陕西汉中723001 西安地球环境创新研究院西安710061 长安大学水利与环境学院西安710054

为了探究纳米C-Co/TiO_(2)催化剂降解五氯苯酚的动力学特性,采用溶胶-凝胶法,制备了C、Co双元素掺杂复合改性的纳米C-Co/TiO_(2)催化剂。利用XRD、SEM-EDS、UV-vis进行表征分析,结果表明:掺杂C、Co元素后,纳米C-Co/TiO_(2)晶型未发生改... 详细信息

为了探究纳米C-Co/TiO_(2)催化剂降解五氯苯酚的动力学特性,采用溶胶-凝胶法,制备了C、Co双元素掺杂复合改性的纳米C-Co/TiO_(2)催化剂。利用XRD、SEM-EDS、UV-vis进行表征分析,结果表明:掺杂C、Co元素后,纳米C-Co/TiO_(2)晶型未发生改变,特征峰强度增强,晶体结晶性好,粒径约为12.08 nm;催化剂表面呈现球状堆积形貌,比表面积大,有利于反应物吸附脱附;与纯TiO_(2)相比,催化剂带隙能降低,对可见光的响应性增强。结合降解过程中产物的紫外吸收光谱,探究五氯苯酚的催化降解机理。根据试验检测结果,分析拟合初始浓度与降解速率的线性关系,得到光催化降解五氯苯酚的L-h模型动力学方程:r0=0.38491 0.0951C_(0)/1+0.0951C_(0)。

关键词：复合改性纳米TiO_(2) 碳钴双掺杂光催化降解五氯苯酚动力学方程

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SK1井套管磨损剩余强度安全评价研究

石油矿场机械 2024年第1期53卷 25-31页

作者：崔国杰许杰曹衍国靳楠赵洪山中海石油(中国)有限公司天津分公司天津300459 中石化胜利石油工程有限公司钻井工艺研究院山东东营257000

深井超深井钻井过程中,受井眼狗腿度、机械钻速、顶驱转速等因素影响,技术套管的磨损问题不容忽视,严重时将会导致其抗外挤、抗内压强度明显降低,对井筒完整性造成极大隐患。为此,结合SK1井244.5 mm技术套管磨损原因深入分析,利用套管... 详细信息

深井超深井钻井过程中,受井眼狗腿度、机械钻速、顶驱转速等因素影响,技术套管的磨损问题不容忽视,严重时将会导致其抗外挤、抗内压强度明显降低,对井筒完整性造成极大隐患。为此,结合SK1井244.5 mm技术套管磨损原因深入分析,利用套管“磨损-效率”理论模型,建立了套管磨损量及剩余壁厚的预测方法,指出套管磨损严重位置通常发生在狗腿度较大的井深处,且随顶驱转速增加和机械钻速降低,套管的磨损量明显增大。通过将磨损套管分别简化成具有内壁不圆、不均度的含缺陷套管及“矩形槽”套管,建立了磨损套管的剩余抗外挤、抗内压强度计算方法及全井段剩余强度安全系数计算方法。分析表明,当顶驱转速高于100 r/min、机械钻速低于0.87 m/h时,SK1井244.5 mm套管的抗外挤最小安全系数将会低于1.0,需采取合理的钻井提速及防磨措施,以保证技术套管的强度安全。研究成果对于今后深井超深井的套管柱安全设计具有重要的指导意义。

关键词：套管磨损磨损预测剩余强度技术套管安全评价

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Assimilation of the Fy-4A AGRI Clear-Sky Radiance Data in a Regional Numerical Model and Its Impact on the Forecast of the“21·7”henan Extremely Persistent heavy Rainfall

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Advances in Atmospheric Sciences 2023年第5期40卷 920-936页

作者： Lan xu Wei ChENG Zhongren DENG Juanjuan LIU Bin WANG Bin LU Shudong WANG Li DONG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Institute of Applied Meteorology Beijing 100029China Key Laboratory of Meteorological Disaster of Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC) Nanjing University of Information Science&TechnologyNanjing 210044China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Public Meteorological Service Center China Meteorological AdministrationBeijing 100081China

Assimilation of the Advanced Geostationary Radiance Imager(AGRI)clear-sky radiance in a regional model is *** forecasting effectiveness of the assimilation of two water vapor(WV)channels with conventional observations for the“21·7”henan extremely.h.avy rainfall is analyzed and compared with a baseline test that assimilates only conventional observations in this *** results show that the 24-h cumulative precipitation forecast by the assimilation experiment with the addition of the AGRI exceeds 500 mm,compared to a maximum value of 532.6 mm measured by the national meteorological stations,and that the location of the maximum precipitation is consistent with the *** results for the short periods of intense precipitation processes are that the simulation of the location and intensity of the 3-h cumulative precipitation is also relatively *** analysis increment shows that the main difference between the two sets of assimilation experiments is over the ocean due to the additional ocean observations provided by Fy-4A,which compensates for the lack of ocean *** assimilation of satellite data adjusts the vertical and horizontal wind fields over the ocean by adjusting the atmospheric temperature and humidity,which ultimately results in a narrower and stronger WV transport path to the center of heavy precipitation in Zhengzhou in the lower ***,the WV convergence and upward motion in the control experiment are more dispersed;therefore,the precipitation centers are also correspondingly more dispersed.

关键词： Fy-4A AGRI clear-sky radiance satellite data assimilation “21·7”henan extremely persistent heavy rainfall

The use of bacterial cellulose from kombucha to produce curcumin loaded Pickering emulsion with improved stability and antioxidant properties

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Food Science and human Wellness 2023年第2期12卷 669-679页

作者： Zhiyu Li Wenxiu hu Jiajia Dong Fidelis Azi Xiao xu Chuanhai Tu Sijie Tang Mingsheng Dong College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China College of Pharmacy Nanjing University of Chinese MedicineNanjing 210023China School of Life Science Shaoxing UniversityShaoxing 312000China College of Food Science and Pharmacy Zhejiang Ocean UniversityZhoushan 316022China

Curcumin is a bioactive molecule with limited industrial application because of its instability and poor solubility in ***,curcumin-loaded Pickering emulsion was produced using purified bacterial cellulose from fermented kombucha(KBC).The morphology,particle size,stability,rheological properties,and antioxidant activities of the curcumin-loaded Pickering emulsion were *** fluorescence microscope and scanning electron microscopy images showed that the curcumin-loaded Pickering emulsion formed circular droplets with good *** curcumin-load Pickering emulsion exhibited better stability under a wide range of temperatures,low p h,sunlight,and UV-365 nm than the free curcumin,indicating that the KBC after high-pressure homogenization improved the stability of the *** encapsulated curcumin retained its antioxidant capacity and exhibited higher functional potential than the free *** study demonstrated that the KBC could be an excellent material for preparing a Pickering emulsion to improve curcumin stability and antioxidant activity.

关键词： Bacterial cellulose Curcumin Pickering emulsion Stability Antioxidant activity

Super-tough and rapidly self-recoverable multi-bond network hydrogels facilitated by 2-ureido-4[1h]-pyrimidone dimers

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Chinese Chemical Letters 2021年第1期32卷 521-524页

作者： hao xu xu-Ming Xie Key Laboratory of Advanced Materials(MOE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Multi-bond network(MBN) hydrogels contain hierarchical dynamic bonds with different bond association energy as energy dissipation units,enabling super-tough mechanical *** this work,we copolymerize a protonated 2-ureido-4[1 h]-pyrimidone(UPy)-contained monomer with acrylic acid in hCl *** removing excess hCl,UPy motifs are deprotonated and from dimers,thus generating an UPy-contained MBN *** obtained MBN hydrogels(75 wt% watercontent) exhibit super-tough mechanical properties(0.39 MPa to 2.51 MPa tensile strength),with tremendous amount of energy(1.68 MJ/m^(3) to 11.1 MJ/m^(3)) dissipated by the dissociation of UPy *** introduction of ionic bonds can further improve the mechanical ***,owing to their dynamic nature,both UPy dimers and ionic bonds can re-associate after being dissociated,resulting in excellent self-recovery ability(around 90% recovery efficiency within only 1 h).The excellent self-recovery ability mainly originates from the re-association of UPy dimers based on the high dimerization constant of UPy motifs.

关键词： Multi-bond network Quadruple hydrogen bonding Self-recovery Super-tough hydrogel 2-Ureido-4[1h]-pyrimidone dimer

白血病抑制因子对牛卵母细胞体外发育能力的影响

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中国畜牧兽医 2024年第2期51卷 462-469页

作者：莫显红陶庆华房义梁婧张佳音梁小航徐振军赤峰学院化学与生命科学学院赤峰024000 福建农林大学动物科学学院(蜂学学院) 福州350002 中国科学院东北地理与农业生态研究所吉林省草地畜牧重点实验室长春130062 内蒙古赛科星家畜种业与繁育生物技术研究院呼和浩特011517

[目的]探究白血病抑制因子(leukemia inhibitory factor, LIF)对牛卵母细胞和早期胚胎发育能力及多潜能基因表达的影响。[方法]将牛卵丘-卵母细胞复合体(cumulus oocyte complexes, COCs)分为4组,对照组:在卵母细胞体外成熟(in vitro ma... 详细信息

[目的]探究白血病抑制因子(leukemia inhibitory factor, LIF)对牛卵母细胞和早期胚胎发育能力及多潜能基因表达的影响。[方法]将牛卵丘-卵母细胞复合体(cumulus oocyte complexes, COCs)分为4组,对照组:在卵母细胞体外成熟(in vitro maturation, IVM)和胚胎体外培养(in vitro culture, IVC)过程中均不添加LIF溶液;处理组1(T1组):IVM过程添加25 ng/mL LIF,IVC过程不添加LIF;处理组2(T2组):IVM过程不添加LIF,IVC过程添加25 ng/mL LIF;处理组3(T3组):IVM和IVC全过程均添加25 ng/mL LIF。用Fluo-3荧光指示剂检测卵母细胞胞内游离钙离子([Ca2+]i)浓度;挑选有第一极体排出的卵母细胞进行孤雌激活,统计各组卵母细胞卵裂率和囊胚率;利用实时荧光定量PCR检测囊胚中多潜能基因的相对表达量。[结果]与对照组相比,培养8 h后,T1组牛卵母细胞胞内[Ca2+]i浓度极显著下降(Ph后,T1组牛卵母细胞胞内[Ca2+]i浓度极显著升高(P<0.01)。T1和T3组孤雌激活后卵裂率和囊胚率均显著高于对照组,且T3组囊胚率显著高于T1和T2组(P<0.05)。实时荧光定量PCR结果显示,T3组囊胚中POU结构域5类转录因子1(POU5F1)和同源框蛋白(NANOG)基因表达量均显著高于对照组,尾型同源盒转录因子2(CDX2)基因表达量显著低于对照组(P<0.05)。[结论]在IVM过程中添加LIF可提高卵母细胞的发育能力,在IVM+IVC全过程添加LIF对早期胚胎发育和多潜能基因的表达有积极作用。

关键词：白血病抑制因子多潜能基因钙离子胚胎发育